Zhangmu (known in Tibetan as Khasa) is the last Chinese town before the border with Nepal, perched at about 2,300 metres on a steep mountainside in a narrow gorge. The town clings to the road in a series of switchbacks, with buildings stacked on top of each other up the hillside — it feels more Nepali than Tibetan, and the climate is noticeably warmer and wetter than the plateau above.
The hills around Zhangmu are heavily wooded, with innumerable waterfalls cascading down the slopes in summer and frozen into spectacular icicles during winter. The town is primarily a trading post and border crossing, busy with trucks carrying goods between China and Nepal. The Sino-Nepal Friendship Bridge lies a few kilometres further down the road, spanning the gorge into Nepal's Kodari village.
Zhangmu was badly damaged by the 2015 Nepal earthquake and was closed for several years. The border has since reopened, but check current conditions before planning to cross here — the road between Zhangmu and the border can be treacherous, especially during the monsoon.