Dunhuang has two unmissable sights — the Mogao Caves and the Singing Sand Dunes with Crescent Lake — and a long list of secondary sights scattered across the surrounding desert. The town itself can be walked in a couple of hours; the rest is half-day or full-day trips out into the Gobi, usually by booked car or organised tour. Plan at least two full days, three if you want to see Yumen Pass and the Yardangs.