The city walls of Shanhaiguan form a rough square enclosing the old town, with a perimeter of around 4 km and gates at the four cardinal directions — the First Pass (east), the South Gate, the West Gate and the North Gate. The walls were built in 1381 under the Ming general Xu Da, restored in the 19th century, and substantially rebuilt as a tourist site in the 1980s and 2000s. The current state is closer to a Ming reconstruction than to the original surviving fabric, but the line and scale are accurate.
Visitors can climb the wall at the First Pass and walk the full circuit if energetic — a complete circuit takes about ninety minutes — or take in shorter sections. The walls give the best sense of the town's planning: the regular grid of streets inside, the moats outside, the alignment with the mountains and the sea. The south-east corner offers the best photograph of the wall meeting the city.