According to Baidu map query, the distance from Xining to Datong is about 4 1.9 km, and the journey takes about 35 minutes, passing through Ninggui Expressway and Ningda Expressway.
From Xining to Datong, you can take bus No.40 at the municipal government station and get off at 8 stops, then take Ningda Hi-Tech at Xinning Road Bus Station and get off at Sanqiao Station after 6 stops. The whole journey takes about 2 hours and 6 minutes.