Lang Son is located far north at the 0 km landmark of National Highway 1A, more specifically at Huu Nghi Quan (Friendship Gate). This is an important transportation link between Vietnam and China. The main ethnic groups found in that area include the Kinh, Tay, Nung, Dao, and Ngai.

The annual average temperature is 21.5°C with an annual humidity of 82%.

Famous tourist sites include Tien Pagoda, Tien Pond, Nhat Thanh Cave, Nhi Thanh Cave, Tam Thanh Cave, and Mau Son Resort.