Mountain Pass Elevation Impact

Driving across Bhutan means crossing high passes. Most are 3,000–4,000 m, and you'll descend back to 1,200–2,300 m valleys. The combination of quick altitude gain + switchback nausea + cold is unique. This page maps the major passes, their elevation, what season closes them, and how they should fit your acclimatization schedule.

Dochula Pass

3,100 m

Thimphu ↔ Punakha. Famous for 108 chortens. Easy stop. Mild altitude exposure.

Year-round Mild

Pele La

3,420 m

Wangdue ↔ Trongsa. Central spine of East–West. Often fogged in. Marked prayer flags.

Year-round Moderate

Chele La

3,888 m

Paro ↔ Haa. Often snowed-in winter (Dec–Feb). Best done on a clear day, ideally mid-trip.

Winter closure risk Moderate

Yotong La

3,400 m

Trongsa ↔ Bumthang descent. Mild pass; main switchbacks above 3,300 m. Spectacular views.

Year-round Mild

Thrumshing La

3,750 m

Bumthang ↔ Mongar. The most dramatic pass. Heavy fog and ice possible Oct–Feb. Lunch at summit.

Winter closures High

Wangthang La

3,400 m

Mongar ↔ Trashigang. Gentler. Often your last pass of the trip.

Year-round Mild

Shertang La

3,575 m

Eastern Bhutan trekking pass — out of mainstream tourist traffic. Permit required.

Restricted High

Kori La

2,450 m

Mongar ↔ Trashigang. Often called a "pass" but is low. No altitude risk.

Year-round Easy

Black Mountain

2,800 m

Between Phobjikha and Trongsa. Gentler; most travelers don't notice it.

Year-round Easy

What this solves

Drivers will tell you passes are scenic stops. They are. They are also where you gain 2,000+ m of altitude in an hour. If you have any altitude sensitivity, plan passes earlier in your trip — not on day 5 when you start a high-altitude trek.

How to use the pass cards

Each card shows altitude, route, and closure risk. Mild passes (under 3,200 m) are comfortable. Moderate (3,200–3,600 m) may give you a short headache. High (3,600+ m) warrants Diamox if you're altitude-sensitive.

Limitations

Real-time closure information is not always available. Confirm with your driver.
Snow happens even in April on Chele La and Thrumshing La — pack a warm layer regardless of season.

FAQ

Which pass is most scenic?

Dochula for the 108 chortens and Himalayan backdrop (clear days only). Thrumshing La for sheer drop drama. Chele La for the Haa Valley view.

Will I get altitude sickness crossing a pass?

Unlikely if you descend back to a valley town the same day. Risk is from sleeping high, not crossing high.

Sources

Department of Roads — Bhutan pass altitude and seasonal closures
Bhutan Mountaineering & Trekking guides (TOAB training manual)