In October 1994 went on a trip to the Karakoram Highway (KKH) which crosses the Karakoram (where K2 is) from Pakistan to Xinjiang province in China. I flew into Karachi and thence to Islamabad, then went overland, spending some time in the silk road oases before getting back via Xi'an and Hong Kong.
The KKH starts near Islamabad and Rawalpindi and winds up through the North-West Froniter Province to the Northern Areas and the Karakoram. The border crossing at the Khunjerab Pass is 4800m high. On the other side, the road descends near Afghanistan and Tajikistan to the Taklamakan ("you go in but don't come out") desert. Around the rim of this lie the oases Kashgar, Aksu and Turphan. Trains leave to the East from Urumchi, the province capital, passing near the Buddhist caves of Dunhuang and through Xi'an where the Silk road starts and the Terracotta warriors can be seen.