What is the elevation of the Gansu section of g2 12 National Highway?

G2 12 journey 1302km, starting from Lanzhou, Lintao, Minxian, Dangchang, Wudu, Wenxian and Guangyuan, Sichuan, and ending in Chongqing. The highest elevation of G2 12 is in Muzhailing, which is the watershed between Tao Wei and Min County, with an altitude of 2,840 meters. Muzhailing Tunnel: The total length is 17 10 meter, the main line is 9 kilometers, the carriageway is 9 meters wide, and the total investment is nearly160 million yuan. The tunnel is located on the eastern edge of the Qinghai-Tibet Plateau, with an altitude of 32 16m, an annual average temperature of 5.5℃ and a minimum temperature of -34.6℃. The frost-free period of the whole year is only 93 days, which belongs to the cold and humid zone. It is an important part of National Highway 2 12 from Lanzhou to Guanzigou, and it is also an important passage from Gansu and Northwest China to Southwest China.