Har Ki Dun Trek Guide: Closures, Osla, and the Real Season

Introduction

Har Ki Dun is a valley trek, genuinely. Not a summit dressed up as one. You walk up the Supin river through deodar forest and terraced fields, past villages built of wood and stone, into a cradle-shaped hanging valley at around 3,566 m with Swargarohini standing at the head of it. There is no top to reach. The valley is the point.

That makes it a different animal from Kedarkantha, which shares the same base village. Kedarkantha is about a summit morning. Har Ki Dun is about five days of walking through inhabited landscape.

Now the thing that decides whether you can go at all.

Har Ki Dun has two closures, not one. The Uttarakhand Forest Department shuts the trek from roughly post-December until mid-March for wildlife migration through Govind Pashu Vihar. Separately, the sanctuary closes for around three months in the monsoon. Stack those and your real trekking windows are March to June and September to November. That is it.

Almost every listicle that puts Har Ki Dun on a "best winter treks in India" roundup is describing a period when the Forest Department has it closed.

Table of Contents

1. Quick Overview
2. The Two Closures — When You Can Actually Go
3. Permits & Booking
4. The Bugyal Camping Ban and the Har Ki Dun Campsite
5. Acclimatisation and Acute Mountain Sickness
6. How to Reach Sankri from Mumbai
7. How to Reach Sankri from Pune
8. The Route: Sankri to Har Ki Dun
9. Osla, Seema and the Duryodhana Tradition
10. Extensions: Jaundhar Glacier, Maninda Tal, Ruinsara Tal
11. Itinerary
12. Accommodation
13. Food
14. Nearby Attractions
15. Budget Breakdown
16. Practical Tips
17. Safety Tips
18. Common Mistakes
19. Best Time to Visit
20. FAQ
21. Conclusion
22. Sources

Quick Overview

Item	Detail
Valley altitude	About 3,566 m (11,700 ft), per Wikipedia
Base village	Sankri, 1,950 m, Mori tehsil, Uttarkashi district
Roadhead beyond Sankri	Taluka, reached by rough jeep track
Protected area	Govind Pashu Vihar National Park and Wildlife Sanctuary
Distance	Indiahikes documents around 37 km over five trekking days on its Kotgaon-based itinerary. Other itineraries from Sankri run 40–48 km depending on the line taken
Duration	Six to seven days from Dehradun
Difficulty	Moderate, suitable for fit beginners. The official park site grades the Taluka to Har Ki Doon route "Easy"
Altitude gain	Indiahikes gives roughly 6,400 ft to 11,600 ft
Winter closure	Post-December to mid-March, for wildlife migration
Monsoon closure	Around three months
Real season	March to June, September to November
Camping in Har Ki Dun itself	Restricted. Alpine meadow
Nearest airport	Jolly Grant, Dehradun
Nearest railway station	Dehradun, about 200 km from Sankri

The valley is snow-covered from October to March per Wikipedia, and connects to the Baspa valley in Himachal over the Borasu Pass. Swargarohini, the peak the Mahabharata associates with the Pandavas' ascent to heaven, dominates the head of the valley.

The Two Closures — When You Can Actually Go

This is the section to read before you book anything, so it goes first.

Closure one: the winter wildlife migration shutdown.

Indiahikes states it directly in its Har Ki Dun documentation: "The forest department of Uttarakhand also shuts the Har Ki Dun trek for visitors post-December until mid-March during the migration of animals in the Govind Pashu Vihar National Park and Wildlife Sanctuary." They add that this has been enforced since December 2016, because the winter migration corridor overlaps the trail, and that the trek reopens in mid-March.

This is the closure nobody mentions. It is also why Indiahikes shifted all their winter Har Ki Dun batches to Kuari Pass. If you are reading a page that recommends Har Ki Dun in January, that page has not been updated in years.

Closure two: the monsoon sanctuary shutdown.

The same Indiahikes documentation notes that the monsoon "arrives, shutting down the Govind Pashu Vihar Sanctuary for about 3 months." No crisp official dates are published anywhere I could find. In practice this means July, August and part of September.

Stack them and here is what is left:

Period	Status
Post-December to mid-March	Closed — wildlife migration
Mid-March to June	Open. Spring and early summer season
July to early or mid-September	Closed — monsoon
Mid-September to November	Open. Post-monsoon season
December	Open until the winter closure kicks in

Two windows a year. Roughly six months of legal trekking.

Why this matters more than it sounds. Har Ki Dun appears constantly in "best winter treks" listicles, usually alongside Kedarkantha, which is in the same sanctuary and is not subject to the winter migration closure. The two treks get lumped together and the closure gets lost. Then people book December-end departures and find out at the check post.

Verify before you book. I have sourced the closure to Indiahikes' current trek documentation, which is the most reliable operator source in Indian trekking and reflects what they are told by the Forest Department. I could not find a published Forest Department notification stating the dates. Confirm with the DFO office at Purola or through gwsandnp.in before you buy flights, and treat "post-December to mid-March" as the working assumption rather than a gazetted date.

Permits & Booking

A forest permit is mandatory. The entire route lies inside Govind Pashu Vihar National Park and Wildlife Sanctuary. Naitwar, on the drive up, marks the start of the protected area, and the trail runs through both buffer and core zones.

Where you get it. At the Sankri forest check post, or from the DFO office at Purola. Operators handle this for their groups. Independent trekkers do it at Sankri.

The official channel. The Govind Wildlife Sanctuary and National Park runs an official website at https://gwsandnp.in listing all its trekking routes, including "Har ki Doon" starting from Taluka, with login, registration and booking sections. Register there. Whatever that portal says overrides operator pages.

The fee: no official published tariff I could verify. The Uttarakhand Forest Department does not publish a Har Ki Dun permit rate on an accessible public page. Operator sources for Govind Pashu Vihar quote in the region of ₹150–300 per person for entry and ₹50–100 per tent per night for camping, with higher rates for foreign nationals, but none cite a departmental order. I am not going to invent a figure. Budget ₹800–1,000 per head across a five-day trek for entry plus camping charges and you will be covered.

Guides. Operator sources state that a registered local guide is required inside the sanctuary and that solo trekkers must engage one certified by the Sankri forest office. I could not verify this against a published order. Assume it applies, and on a five-day trek through a wildlife corridor you want a local guide regardless.

What to have ready:

• Government photo ID, originals and copies, for every person.
• Cash. Purola has the last ATM before Sankri, per Wikipedia.
• Everything you carry in, you carry out. Core national park zone.

Signal. Sankri is the last place with a stable mobile signal, per Wikipedia. Indiahikes notes electricity at the villages higher up is intermittent and can be absent for most of the day. Charge everything at Sankri, carry a power bank, and tell someone your itinerary before you walk.

The Bugyal Camping Ban and the Har Ki Dun Campsite

Worth understanding, because it changed where you sleep.

The Uttarakhand High Court at Nainital, on 21 August 2018, deciding a PIL brought by the Aali-Bedini-Bagzi Bugyal Sanrakshan Samiti, banned night stay by tourists in Uttarakhand's alpine and sub-alpine meadows and capped visitors at 200 per day, plus ordering removal of permanent structures from the bugyals and an end to commercial grazing.

Har Ki Dun itself is an alpine meadow. Indiahikes recorded the consequence at the time: the final Har Ki Dun campsite was dropped, and trekkers instead camp lower and walk up to Har Ki Dun and back as a day excursion.

Their current itinerary still reflects that structure: camp at Boslo at around 10,502 ft, then a day trip up to Har Ki Dun at 11,600 ft and back down. Same valley, same views, you just do not sleep in it.

So what should you do with this information? Accept it. The day-excursion structure is honestly a better way to see the valley anyway, because you arrive rested and you are not scrambling to pitch tents at 3,566 m. And if an operator offers you a night camped in Har Ki Dun itself, ask them directly how that complies with the court's order.

I found no credible report that the 2018 order has been stayed or set aside, though the Uttarakhand government said in June 2019 it intended to appeal to the Supreme Court. The operating reality on the ground still reflects the restriction.

Acclimatisation and Acute Mountain Sickness

Har Ki Dun tops out around 3,566 m, and the extensions go higher. That is enough altitude to matter.

The profile is gentle, which helps. Indiahikes describes the trek as gaining roughly 5,500 ft over five trekking days, from about 6,400 ft to 11,600 ft. That is a slow, staged ascent through inhabited valleys, which is close to ideal for acclimatisation. Har Ki Dun is one of the kinder Himalayan treks in this respect.

Where it still catches people out. A group that flies into Dehradun, drives ten hours to Sankri, sleeps badly, and starts walking the next morning has compressed the low-altitude part. And the extensions — Jaundhar Glacier, Ruinsara Tal, Maninda Tal — take you meaningfully higher, often on a day when you feel invincible.

Symptoms. Headache first, usually with nausea or appetite loss, unusual fatigue, dizziness, or disturbed sleep. It is not the same as being tired. Tired resolves when you rest.

The two emergencies. HAPE: breathlessness at rest, wet cough, chest tightness. HACE: confusion, poor coordination, inability to walk a straight line. Both need immediate descent, whatever the hour.

Practical measures for this trek specifically:

• Sleep a full night at Sankri. Not a four-hour stop. This is the acclimatisation night.
• Do not skip the intermediate camps. Operators offering compressed itineraries are removing your acclimatisation.
• Three to four litres of water a day. Cold air and exertion dehydrate you quietly.
• Eat properly at camp. Appetite drops at altitude. Push through it.
• Be careful on the excursion day. Boslo or Simatra to Har Ki Dun and back is the day you gain the most height. Go slow.
• Think twice about extensions if anyone is feeling off. Jaundhar Glacier is not the place to test a headache.
• No alcohol.
• Descent is the treatment. There is a real advantage here: the trek has only one exit, retracing to Taluka and Sankri, and every step of it is downhill. Use it early rather than late.

On acetazolamide (Diamox). Prescription medicine, real side effects. Talk to a doctor before you go.

If your entire trekking background is Maharashtra forts, read Sahyadri trek versus Himalayan trek before you come. Fitness and altitude tolerance are different things.

How to Reach Sankri from Mumbai

Everything goes through Dehradun. Sankri is about 200 km beyond it and Wikipedia is blunt: "One has to go through Dehradun to reach Sankri."

Route A — fly to Dehradun. Direct Mumbai to Jolly Grant (DED) flights operate daily, roughly two and a half hours. Land in the morning, sleep in Dehradun, and take the road to Sankri at first light the next day. Trying to fly in and drive to Sankri the same day only works with a very early flight, and it means arriving in the dark.

Route B — train to Dehradun. Direct services run from Mumbai. Long — broadly 28 to 35 hours depending on the train. Cheap and it puts you exactly where you need to be. For a group of six with time and no budget, this is a reasonable choice.

Route C — fly to Delhi, then overland. More flight options. Then an overnight train or a Volvo bus to Dehradun. Costs you a night, saves you money.

The road leg. Dehradun to Sankri, roughly 200–210 km via Mussoorie, Nainbagh, Naugaon, Purola, Mori and Naitwar. Eight to ten hours. Indiahikes runs a shared vehicle on this route and prices it at ₹1,300 plus GST per trekker one way, ₹2,600 return, which is a reasonable benchmark for what a seat should cost. A private vehicle for the whole run costs about ₹6,000 one way.

Going independently: shared jeeps run Dehradun to Purola, Purola to Mori, Mori to Naitwar, Naitwar to Sankri. The Dehradun to Purola jeeps thin out badly after mid-afternoon. Start at dawn or expect to sleep in Purola.

Beyond Sankri. The Har Ki Dun trail proper starts at Taluka, about 11–12 km up a rough track from Sankri. Jeeps run it when the track is passable, which it often is not after rain. Indiahikes describes it as a landslide-prone route frequently closed during the monsoon. Some itineraries build in the walk from Sankri to Taluka rather than depend on the jeep.

How to Reach Sankri from Pune

Pune → Dehradun by air. Direct flights operate on most days. Fastest, and given how much of this trip is spent in vehicles, worth the fare.

Pune → Delhi → Dehradun. Fly to Delhi, then overnight train or bus. Most flexible on dates.

Pune → Haridwar or Dehradun by train. Direct services exist and run past 30 hours. From Haridwar, Dehradun is an hour and a half further, and the shared jeep network to Purola runs out of Dehradun.

Realistic Pune shape: fly Friday morning, sleep in Dehradun, drive Saturday, trek Sunday to Thursday, drive out Friday, fly home Friday night. That is eight days with no buffer. Nine days is safer.

The Route: Sankri to Har Ki Dun

Distances vary by operator because they use different start points and different intermediate camps. Indiahikes builds its itinerary from Kotgaon and totals around 37 km over five trekking days. Routes described from Sankri run longer. The shape is consistent.

Sankri to Taluka. 11–12 km of rough jeep track along the Supin, or a walk if the track is out. Taluka sits at roughly 6,900 ft. This is where the trail proper begins.

Taluka to the first camp — through the villages. The trail follows the Supin river through deodar forest and past the villages of Dhatmeer, Dharkot, Gangad and Osla. This is the section that makes the trek. Wooden Garhwali houses with carved beams, terraced fields cut into the slope, apple orchards, and people going about their lives rather than performing for tourists. Common camps here are Gangad, Puani Garaat or Osla.

Osla and Seema. Osla sits on one side of the Supin at around 2,590 m; Seema is across the river, and it is where the forest rest house and most trekker camps are. The two get used interchangeably in itineraries and they are not the same place. Indiahikes notes that from the Puani Garaat area you can trek up the true right of the river to Seema, then cross a bridge over the Thumsa. If you want to camp at Osla itself you cross a wooden bridge.

Into the upper valley. Above Osla the trail climbs to the meadows. Kalkatiyadhar sits around 9,983 ft on the Indiahikes line; Devsu Thatch is a broad meadow at about 9,878 ft; Boslo is at 10,502 ft in forest, and Indiahikes rates it their favourite campsite on the trek.

The valley day. From Boslo, or from Simatra on other itineraries, you walk up to Har Ki Dun at about 11,600 ft and return the same day. Indiahikes gives 10.5 km and about 6 hours for the round trip from Boslo, with a ridge walk that gets tricky in places before it flattens out.

This is the day the trek exists for. Cradle-shaped hanging valley, Swargarohini at the head of it, the Hatta peaks along one side and the ground running away towards Ruinsara on the other. Wikipedia notes there is a temple dedicated to Shiva in the final village along the trek.

The return. Boslo to Devsu Thatch, then down through the villages to Taluka, and out to Sankri. Indiahikes is explicit that this trek has only one exit — you retrace to Taluka and Kotgaon. There is no alternative way off the mountain. Factor that into how you think about risk.

Osla, Seema and the Duryodhana Tradition

This is why a lot of people choose Har Ki Dun over Kedarkantha, and it deserves care rather than a breathless paragraph.

Osla is a village of traditional wooden and stone houses at around 2,590 m, reached by trekking 13–14 km from Taluka. It is the last village on the Har Ki Dun route. The architecture alone is worth the walk: multi-storey timber construction with carved facades, the sort of thing that has been replaced by concrete almost everywhere else in Garhwal.

The temple. Osla has an ancient three-chambered wooden temple. It is officially named the Someshwar Temple and dedicated to Shiva. Local tradition holds that it is a temple to Duryodhana, the Kaurava prince of the Mahabharata, and the village has long been associated with his worship.

I want to be precise about the status of that claim.

This is living local tradition, not established history. There is no archaeological or textual evidence establishing a Mahabharata-era temple here, and the frequently repeated "5,000-year-old ritual" figure is a claim of tradition, not a dated finding. The upper Tons basin developed a distinct religious culture in relative isolation, in which both Pandavas and Kauravas feature, and that is genuinely unusual in India, where the Pandavas are almost universally the revered side. Sources also record that the temple has been officially designated Someshwar and re-dedicated to Shiva while the Duryodhana association persists locally.

Treat all of that as what it is: a fascinating and well-attested contemporary tradition with a contested and undocumented origin story. Do not go around telling people it proves the Pandavas walked this valley. Also do not dismiss it, because the tradition itself is real and the village takes it seriously.

How to behave in Osla. Ask before photographing people or the temple interior. Non-locals are not always welcome inside village shrines in the upper Tons and that is their call, not yours. Do not treat a working village as a photo set. Buy tea, pay for it properly, and do not haggle over forty rupees with someone whose entire cash economy runs on trekkers for six months a year.

Seema, across the river, is where the forest rest house sits and where most groups actually camp. Indiahikes notes the temple in the village is often found closed.

Extensions: Jaundhar Glacier, Maninda Tal, Ruinsara Tal

Har Ki Dun is a hub, not a dead end.

Jaundhar Glacier. Beyond Har Ki Dun, a further climb up the valley. Indiahikes describes the view of the Jaundhar glacier along with the Hatta peaks and Maninda Tal from high on the trek. It is an extension day and it takes you meaningfully higher, so it depends on how the group is handling altitude. Indiahikes' position when the meadow ban forced itinerary changes was that the trek leader would take a call on Jaundhar Glacier or Maninda Tal based on weather and conditions. That remains the right way to treat it: not a guarantee, a decision made on the day.

Maninda Tal. A lake beyond Har Ki Dun, from where the Thumsa originates. The official park website lists a Maninda Pass route from Harkidun and grades it "Easy", which tells you something about how the department views the terrain rather than the effort.

Ruinsara Tal. A separate valley branching off before Har Ki Dun. The official park site lists a Ruinsara route from Osla and grades it "Easy". It is commonly done as a combined Har Ki Dun and Ruinsara itinerary of eight or nine days, and it is quieter than the main valley. It also connects onward to Bali Pass, which is a serious undertaking and graded "Tough" by the park.

Borasu Pass connects Har Ki Dun to the Baspa valley in Himachal. That is an expedition, not an extension.

If you are adding any of these, add days. Do not add them to a fixed itinerary and try to make up time.

Itinerary

The standard seven-day version from Dehradun.

Day 1 — Dehradun to Sankri, 200 km, 8–10 hours. Leave by 6 am. Permits and registration. Sleep at 1,950 m.

Day 2 — Drive Sankri to Taluka on the rough track, then trek to Gangad or Puani Garaat through the villages. 5–6 hours.

Day 3 — Trek to Osla or Seema, then on to the upper camps. Villages, deodar forest, the Supin below you the whole way.

Day 4 — Climb to the meadow camps, Kalkatiyadhar or Boslo. Around 9,900–10,500 ft.

Day 5 — The valley day. Up to Har Ki Dun at about 11,600 ft and back to camp. Around 10.5 km, 6 hours. Add Jaundhar Glacier or Maninda Tal here if the leader calls it on.

Day 6 — Descend through Devsu Thatch and the villages to the lower camps.

Day 7 — Trek to Taluka, drive to Sankri, or continue to Dehradun if the road is behaving.

Day 8 — Sankri to Dehradun.

Add travel days from Mumbai or Pune at each end, plus one buffer day. That is ten days for a comfortable trip, or eight if you fly both ways and accept that a landslide will cost you a flight.

With Ruinsara Tal: add two days. With Jaundhar Glacier: add one.

Accommodation

Sankri. Guest houses and homestays, functional and basic. Bucket hot water. Intermittent electricity. Most operators have a fixed arrangement here.

On the trail. Tents at designated campsites — Gangad, Puani Garaat, Kalkatiyadhar, Devsu Thatch, Boslo, Simatra, depending on which itinerary you are on. There is a forest rest house at Seema, which some independent trekkers use.

Homestays in the villages. Osla and Gangad have a small amount of homestay capacity, and staying in one is a very different experience from a tent. Arrange it in advance through your operator or a Sankri contact; do not turn up expecting a room.

In Har Ki Dun itself. No. Alpine meadow, restricted under the 2018 court order.

Purola and Mori. Fallback if the road defeats you. Purola is bigger and has the last ATM.

Food

Sankri guest houses feed you well: dal, rice, roti, sabzi, rajma, and continuous chai.

On the trail with an operator you eat at camp — hot breakfast, packed lunch, soup and dinner. Independent trekkers carry food from Sankri or arrange a cook and porter there. There are small shops in the villages selling biscuits, Maggi and basic supplies, but do not build a five-day food plan around them.

Water: streams along the route, and the Supin the whole way up. Purify anything you take from a stream below a village. There are people and livestock upstream of you for most of this trek, which is precisely the thing that makes the walk interesting and the water untrustworthy.

Carry ORS sachets, dry fruit, chocolate and something salty. Eat at altitude even when you do not want to.

Nearby Attractions

• Kedarkantha — the summit trek from the same base village. Different trek, different season profile, and not subject to the winter migration closure. Our Kedarkantha trek guide covers it.
• Ruinsara Tal — the quieter parallel valley, from Osla.
• Taluka — the roadhead, worth a walk around.
• Naitwar — where Govind Pashu Vihar begins, at the Rupin–Supin confluence.
• Mori and the Tons river — Tons rafting is serious water, considerably harder than the standard Rishikesh runs.
• Purola — market town, last ATM, decent overnight stop.
• Mussoorie — on the way out, if you have an afternoon before a flight.

Budget Breakdown

Two people, ten days, from Mumbai, through an operator. Indicative, not quoted rates.

Item	Budget (₹)	Mid-range (₹)
Mumbai–Dehradun return, per person	2,400 (sleeper train)	13,000 (flight)
Dehradun–Sankri return transport, per person	2,600 (shared seat)	6,000 (private share)
Operator trek fee, 6–7 days, per person	11,000	16,000
Forest permit and camping charges, per person	see note	see note
Backpack offloading, optional, per person	0	2,100
Gear rental, per person	800	2,500
Meals off-trek, per person	1,500	3,000
Buffer day, per person	1,500	3,000

Permit: no official published tariff I could verify. Operator sources for Govind Pashu Vihar quote roughly ₹150–300 entry plus ₹50–100 per tent per night, uncited. Packages usually include it. Confirm before you pay.

Indiahikes prices its Dehradun–Sankri shared transport at ₹1,300 plus GST one way and backpack offloading at ₹2,000 plus GST for the trek, which are useful benchmarks even if you book elsewhere.

Practical Tips

Confirm the closure dates before you buy a flight. This is the single most important line on this page. Post-December to mid-March is shut, and roughly three monsoon months are shut. Call the DFO office at Purola or check gwsandnp.in.

Sleep a full night at Sankri before you start.

Draw cash at Purola. Sankri has no ATM.

Charge everything at Sankri and carry a power bank. Village electricity above Sankri is intermittent and often absent for most of the day.

Tell someone your route from Sankri, because that is where the signal ends.

The Taluka track is landslide-prone. Have a plan for walking the 11–12 km from Sankri if the jeeps are not running.

Water purification. There are villages and livestock upstream of you.

Trekking poles. Long descending days on rough village paths.

Rain gear from mid-September and in the shoulder weeks of spring. This valley gets weather.

Ask before photographing people, houses or shrines in Osla and Gangad. These are homes.

Carry your waste out, including at village campsites. Core national park.

Build a buffer day. Uttarakhand roads will find it.

Our first aid kit for Sahyadri treks is a good base list; add altitude items and a proper blister kit for a five-day walk.

Safety Tips

One exit. Indiahikes is explicit that Har Ki Dun's only emergency exit is retracing your route to Taluka and Kotgaon. There is no alternative valley to drop into. That changes the arithmetic on every decision: if somebody is unwell at Boslo, getting them out is two days, not two hours. Decide early.

Altitude. See the AMS section. The trek's slow profile helps, the extensions do not.

River crossings and the Supin. You walk beside a substantial Himalayan river for days. It is high and fast in spring melt and after rain. Do not cross anywhere except at the bridges, and do not swim.

The Taluka road. Landslide-prone, frequently closed in monsoon. This is a genuine hazard, not an inconvenience.

Weather in the upper valley. Har Ki Dun at 3,566 m gets snow from October and the weather comes in fast. Cold, wet and windy at 11,600 ft with a group in cotton is the classic Indian trekking failure.

Wildlife. Govind Pashu Vihar holds snow leopard, Himalayan black bear, Himalayan tahr, musk deer, serow and common leopard. The winter closure exists precisely because this is a migration corridor. Encounters are rare. Do not leave food in tents and do not wander off the trail at dusk.

Group discipline. Long days, villages, distractions. Headcounts at every stop. Group trekking safety rules has the framework.

Turning back. With a single exit and two days of walking behind you, the decision to turn a group around gets emotionally harder the further in you are. Read when to cancel or turn back from a trek before you go, not at Boslo.

Insurance with evacuation cover. For a trek with one exit and no road access, this actually matters. Trek insurance explained covers what to look for.

Emergency. 112, when you have signal. You will not have signal.

Common Mistakes

Booking Har Ki Dun as a winter trek. The Forest Department shuts it from post-December to mid-March for wildlife migration. This is the mistake that ruins whole trips.

Trusting a listicle that groups it with Kedarkantha. Same base village, same sanctuary, different closure rules.

Assuming the Taluka jeep will run. It is a landslide-prone track and it is often out.

Expecting to camp in Har Ki Dun itself. Alpine meadow. Restricted since 2018.

Adding Ruinsara or Jaundhar without adding days.

Treating Osla as a photo opportunity. It is somebody's village.

Repeating the Duryodhana story as established history. It is a living local tradition with no documented origin. Say so.

No cash past Purola.

No buffer day.

Drinking unpurified stream water below a village.

Best Time to Visit

Mid-March to April — spring, and the best of the two windows in my view. The trek reopens mid-March after the wildlife closure. Snow lingers in the upper valley, the lower forests come alive, and the villages are at their most photogenic as the fields are prepared. Cold at night. Fewer people than the autumn rush.

May to June — the busy season and the comfortable one. Warmer, long days, meadows green, everything running. This is when families and larger groups come. Book ahead.

July to early or mid-September — closed. Monsoon. The sanctuary shuts for around three months and the Taluka track slides. There is no argument for coming.

Mid-September to October — the clearest air of the year. Post-monsoon, the valley lush from the rain, visibility at its best, Swargarohini sharp against the sky. Indiahikes notes September turns the valley properly green. If views are your priority, come now.

November — cold, clear, emptying out. Snow starts appearing high up. Beautiful and quiet, and you need proper insulation.

December — the window closes. The trek is open at the start of the month and then the winter migration closure comes in. Do not plan a trip that straddles the changeover.

Post-December to mid-March — closed. Wildlife migration through Govind Pashu Vihar. Go to Kedarkantha instead, or to Kuari Pass or Brahmatal territory style winter alternatives.

FAQ

Q: When is the Har Ki Dun trek open? A: Roughly mid-March to June and mid-September to December. The Uttarakhand Forest Department shuts the trek from post-December until mid-March during wildlife migration in Govind Pashu Vihar, and the sanctuary separately closes for about three months in the monsoon. Confirm with the DFO office at Purola before booking.

Q: Can I do Har Ki Dun in winter? A: No, not in the deep-winter months. The trek is closed post-December to mid-March for the wildlife migration. Articles listing it as a winter trek are out of date. Kedarkantha, from the same base village, is not subject to that closure.

Q: How high is Har Ki Dun? A: The valley sits at about 3,566 m (11,700 ft) per Wikipedia. Indiahikes gives 11,600 ft for the point trekkers reach. It is snow-covered from October to March.

Q: How difficult is the Har Ki Dun trek? A: Moderate and suitable for fit beginners. Indiahikes puts it at around 37 km over five trekking days with roughly 5,500 ft of gain, and the official Govind Wildlife Sanctuary site grades the Taluka to Har Ki Doon route "Easy". The difficulty is in the duration and the remoteness, not the terrain.

Q: Do I need a permit? A: Yes. The whole route is inside Govind Pashu Vihar National Park and Wildlife Sanctuary. Permits are obtained at the Sankri forest check post or the DFO office at Purola, and the park's official site at gwsandnp.in handles registration.

Q: What does the permit cost? A: I could not find an official published tariff on any Forest Department page. Operator sources for Govind Pashu Vihar quote roughly ₹150–300 per person plus ₹50–100 per tent per night, without citing a departmental order. Budget ₹800–1,000 per head for a five-day trek and confirm at Sankri.

Q: Is there really a Duryodhana temple at Osla? A: Osla has an ancient three-chambered wooden temple, officially named the Someshwar Temple and dedicated to Shiva, which local tradition associates with the worship of Duryodhana. That association is a living local tradition. There is no archaeological or textual evidence establishing it as historically a Duryodhana temple, and the frequently quoted "5,000-year-old" figure is a claim of tradition rather than a dated finding.

Q: Can I camp in Har Ki Dun valley itself? A: The Uttarakhand High Court's 21 August 2018 order banned night stay in the state's alpine and sub-alpine meadows. Har Ki Dun is an alpine meadow and the final campsite there was dropped as a result. The standard structure now is to camp lower, at Boslo or Simatra, and walk up to Har Ki Dun and back in a day.

Q: What extensions are possible? A: Jaundhar Glacier and Maninda Tal beyond Har Ki Dun, and Ruinsara Tal as a branch from Osla. The park's official site lists Ruinsara from Osla and Maninda Pass from Harkidun. Bali Pass, from the same area, is a serious undertaking graded "Tough". Add days for any of them.

Q: How do I reach Sankri from Mumbai? A: Fly or take a train to Dehradun, then roughly 200–210 km by road via Mussoorie, Purola, Mori and Naitwar, taking eight to ten hours. Sankri is the last roadhead. Beyond it, a rough 11–12 km jeep track runs to Taluka where the trail starts.

Q: What is the emergency exit? A: There is only one. You retrace your route to Taluka and Sankri. Plan accordingly.

Conclusion

Har Ki Dun is the best cultural trek in Garhwal and one of the few Himalayan routes where the walking between the camps is as interesting as the destination. Deodar forest, the Supin running alongside you, terraced fields, and villages of carved wooden houses where the Mahabharata is remembered from an angle nobody else in India uses.

The valley at the end, cradled under Swargarohini, is worth all five days. You will not sleep in it, and that is a good rule that should stay.

The whole thing turns on timing. Two windows a year: mid-March to June, and mid-September to December. Everything else is closed, either for wildlife migration or for monsoon. Get that right and everything else is manageable. Get it wrong and you find out at the Sankri check post, 210 km up a mountain road, having burned three days getting there.

Go in late March if you want snow on the peaks and quiet trails, or in October if you want the clearest air of the year. Add Ruinsara if you have the days. Ask before you photograph anyone in Osla.

Call to Action

Doing both treks from Sankri in one trip? Read our Kedarkantha trek guide for the summit half. New to altitude? Start with Sahyadri trek versus Himalayan trek, then check your cover with trek insurance explained.

Image Alt Text Suggestions

1. Har Ki Dun valley under Swargarohini peak, Uttarkashi district
2. Traditional carved wooden houses at Osla village on the Har Ki Dun trail
3. Someshwar Temple at Osla, associated in local tradition with Duryodhana
4. Deodar forest along the Supin river between Taluka and Gangad
5. Terraced fields above the Supin valley on the Har Ki Dun route
6. Boslo campsite in forest at 10,502 feet, Har Ki Dun trek
7. Devsu Thatch meadow on the descent from Har Ki Dun
8. Jaundhar Glacier seen from the upper Har Ki Dun valley
9. Rough jeep track from Sankri to Taluka in Govind Pashu Vihar
10. Forest rest house at Seema across the Supin from Osla
11. Sankri village, base for Har Ki Dun and Kedarkantha treks
12. Ruinsara Tal, the quieter valley branching from Osla

Sources

1. Har Ki Doon — Wikipedia (valley at about 3,566 m / 11,700 ft, cradle-shaped hanging valley, Borasu Pass connection to Baspa valley, snow-covered October to March, Purola as last ATM, Sankri as last stable mobile signal, Shiva temple in the final village): https://en.wikipedia.org/wiki/Har_Ki_Doon
2. Sankri — Wikipedia (1,950 m, Mori tehsil, Uttarkashi; no road beyond Sankri; route via Dehradun; Har Ki Dun villages Taluka, Dhatmeer, Gangad and Osla; Supin river): https://en.wikipedia.org/wiki/Sankri
3. Har Ki Dun Trek documentation — Indiahikes (Forest Department closure post-December to mid-March for wildlife migration, enforced since December 2016, reopening mid-March; monsoon shutdown of Govind Pashu Vihar for about 3 months; ~37 km over five trekking days; 6,400 ft to 11,600 ft; Boslo, Kalkatiyadhar and Devsu Thatch altitudes; single emergency exit; Dehradun–Sankri transport pricing; landslide-prone Taluka route): https://indiahikes.com/har-ki-dun
4. "All winter trek batches to Har Ki Dun shifted to Kuari Pass" — Indiahikes: https://indiahikes.com/blog/winter-trek-update
5. "Latest Updates About Treks Affected By High Court Order" — Indiahikes (Har Ki Dun final campsite dropped as an alpine meadow; day excursion structure; Jaundhar Glacier and Maninda Tal treated as leader's call): https://indiahikes.com/blog/latest-updates-about-treks-affected-by-high-court-order
6. Aali Bedini Bagzi Bugyal Sanrakshan Samiti vs State of Uttarakhand and Others, Uttarakhand High Court at Nainital, Writ Petition (PIL) No. 123 of 2014, decided 21 August 2018: https://indiankanoon.org/doc/147330564/
7. "Uttarakhand govt to challenge high court ban on night stay in Himalayan meadows" — PTI via Business Standard, June 2019: https://www.business-standard.com/article/pti-stories/uttarakhand-govt-to-challenge-high-court-ban-on-night-stay-in-himalayan-meadows-119062501270_1.html
8. Govind Wildlife Sanctuary & National Park — official website, Uttarakhand Forest Department (park notification history and areas; "Har ki Doon" route from Taluka graded Easy; Ruinsara route from Osla; Maninda Pass from Harkidun; Bali Pass graded Tough; registration and booking): https://gwsandnp.in/
9. Govind Wildlife Sanctuary & National Park, trekking routes list: https://gwsandnp.in/treks.php
10. Govind Pashu Vihar National Park — Wikipedia: https://en.wikipedia.org/wiki/Govind_Pashu_Vihar_National_Park
11. "What Makes The Har Ki Dun Trek One Of The Richest Cultural Experiences" — Indiahikes, on the upper Tons valley's distinct tradition of worshipping both Pandavas and Kauravas: https://indiahikes.com/blog/culture-on-har-ki-dun-trek
12. Uttarkashi district administration, flora and fauna: https://uttarkashi.nic.in/flora-and-fauna-uttarkashi/

The winter migration closure is sourced to Indiahikes' current trek documentation, not to a published Forest Department gazette notification, which I could not locate. The monsoon closure has no crisply published dates either. Both closures are the working reality on the ground. Confirm your dates with the DFO office at Purola or through gwsandnp.in before you book travel.