Mountain and Adverse Weather Driving
Mountain roads demand humility
Bhutan's highways climb steeply, hug cliffs and narrow to single-lane sections. Keep left, especially on blind bends where an oncoming truck may be wide. On single-lane stretches, the vehicle with the easier reversing position or the descending vehicle may need to yield - check signage and local practice, and reverse only with a guide if visibility is poor. Use lower gears for both climbs and descents, and give stalled vehicles room.
Rain, fog and slippery surfaces
Wet roads reduce grip and lengthen stopping distances. Reduce speed, increase following distance, brake gently and avoid sudden steering. In fog, use low-beam or fog lights, not high beam, which reflects back and blinds you. Use the road edge or centre line as a guide but never stare at it. Aquaplaning happens when tyres lose contact with water - ease off the accelerator and avoid braking hard.
Landslides, rockfall and river crossings
After heavy rain, expect landslides, washed-out sections and falling rocks. Do not stop under overhanging rock or on recent debris. Cross flooded sections only if you are certain of depth and the roadbed; fast water can sweep a vehicle away. If in doubt, turn back.
Snow, ice and altitude
On icy sections, drive slowly, use gentle inputs and avoid braking on bends. Snow chains may be needed. At altitude, vehicles lose power and drivers can suffer fatigue or altitude sickness; take breaks.
Traps in exam questions
- High beam in fog is wrong.
- Braking hard while aquaplaning is wrong; ease off instead.
- "Speed up to get through water" is dangerous and wrong.
- Overtaking on a narrow cliff road is almost never the right answer.
Rule of thumb
If you cannot see a safe way through, stop or turn back. No destination is worth a landslide.