Chongqing Rail Transit Line 4 is the eighth urban rail transit line in Chongqing, China, with its identifying color being sun orange. The section from Beizhan North Square Station to Tangjiatan Station was opened for trial operation on December 28, 2018; the section from Beizhan North Square Station to Min'an Avenue Station was opened for trial operation on January 11, 2019; and the section from Tangjiatan Station to Huangling Station was opened for trial operation on June 18, 2022.