雁门关
The complex of fortifications in the Yanmen Pass forms part of the defenses of the "inner line" of the Great Wall, along with the Ningwu and Pianguan Passes. Yanmen was formerly reckoned as the first of the "Nine Passes under Heaven". The preserved Ming fortifications are about long and high. It includes three fortified gatehouses. The western gate is called Dili ("Chosen Battleground"), the central gate is Yanmen proper, and the eastern gate is Tianxian ("Impregnable Fortress"). They are open to the public from 8am to 6:30pm.