The sloped, rectangular wall is 14 kilometers and encloses the old center of Xi'an. That makes it the longest intact city wall in China (and the world)
The top of the wall is like a wide roadway (even broader than the section of Great Wall that we visited). It was designed to allow a large number of soldiers to move rapidly to any section that was being attacked. Today, the roadway is a promenade enjoyed by strolling tourists (good views of the city from atop) and cyclists (you can rent bikes on the wall, if you start from the south gate)