Tànchāng

Tanchang lies in the mountain country of southern Gansu, within the broader Longyou region and the approaches associated with Minzhou. Valleys provide cultivable ground and routes through a landscape of steep slopes and forested uplands. Farming, herding, and woodland resources supported communities whose opportunities varied sharply with elevation and access to water. Paths through this country linked the northwestern Chinese interior with routes toward Sichuan and the Tibetan borderlands.

The wider region brought together Chinese administrative institutions and communities with Tibetan and other cultural connections. Hadapu, in the present county, became known as a trading centre for medicinal herbs during the Ming and Qing periods. The history of specific settlements and the boundaries of earlier administrative units should not be assumed to match the modern county.