Children play roll-skating in Chengdu. [Photo/Chinanews]

Hangzhou and Ningbo, in East China's Zhejiang province came in second and third on the list of happiest cities. Cities that make up the rest of the list are, in order: Nanjing, Changchun, Xi'an, Changsha, Taizhou, Tongchuan and Xuzhou.

Noticeably, the 10 happiest cities in 2017 are all second and third-tier cities, excluding Beijing and Shanghai, the two world-known metropolises. The two both appeared on 2015 and 2016 lists, but dropped off this year's list for reasons that include increasing stress, pollution and traffic.