East over the Pele La to Trongsa
The longest drive of the trip and the one that changes the journey. The road climbs out of the Punakha valley past Wangdue Phodrang — whose dzong burned in 2012 and has been rebuilt — then up through dwarf bamboo to the Pele La at about 3,420 metres, the traditional boundary between western and central Bhutan.
Beyond the pass, Chendebji Chorten stands beside the river, built in the Nepalese style in the eighteenth century. Trongsa appears long before you reach it: the dzong is strung along a spur above the Mangde Chhu gorge, and the road spends half an hour working around the valley to get to it.
Trongsa Dzong was built in 1648 and controlled the only east–west route through the country. Both the first and second Kings ruled from here, and the crown prince still holds the title of Trongsa Penlop before accession.
Note. The Pele La can hold snow in January and February. Closures are brief but they happen.