I'm thinking of the Kremlin in Russia, where, in the Middle Ages, Moscow was a typical town-fortress. Or Rothenburg--Germany's best-preserved walled town. In both these instances, the walls are about one and a half miles long.
We left Qingdao and continued our China adventure in Qufu, which was surrounded by a wall. And we also visited Beijing's Forbidden City, which has a wall over two miles long, forty feet high, thirty feet thick at the base and twenty feet wide on the top.
And then we came to Xi'an, which has the most complete city wall that has survived in China. And Xi'an's city wall is also one of the largest ancient military defensive systems in the world.
The Xi'an city wall is eight and a half miles long, forty feet high, fifty-five feet thick at the base and forty-five feet wide on the top.
