After the 1934 to 1935 Long March, Yan'an served as the CCP's rural headquarters from 1937 to 1947, where Mao wrote On Contradiction, On Practice, and the Yan'an Talks on literature. 'Yan'an spirit' (
延安精神) remains a foundational brand in PRC political discourse. The city's yellow-loess hillside caves (
窑洞) are a major red-tourism site.
