Beijing's
二环路, opened in 1992, traces the footprint of the demolished Ming-Qing inner city wall. The line of today's
东直门,
朝阳门,
崇文门,
宣武门,
阜成门 stations of Subway Line 2 corresponds to the old gates. Many Chinese cities copied the scheme: Chengdu, Xi'an, Wuhan and others all have
一环,
二环,
三环 and beyond.
