Lonely Planet review
Xī'ān is one of the few cities in China where the old city walls are still standing. Built in 1370 during the Ming dynasty, the 12m-high walls are surrounded by a dry moat and form a rectangle with a perimeter of 14km.
Most sections have been restored or rebuilt, and it is now possible to walk the entirety of the walls in a leisurely four hours. You can also cycle from the South Gate (bike hire Y20 for 100 minutes, Y200 deposit). The truly lazy can be whisked around in a golf cart for Y200. Access ramps are located inside the major gates, with the exception of the South Gate, where the entrance is outside the walls; there's another entrance inside the walls beside the Forest of Stelae Museum.
To get an idea of Xī'ān's former grandeur, consider this: the Tang city walls originally enclosed 83 sq km, an area seven times larger than today's city centre.