What are the main county-level cities in Chongqing?

Chongqing covers an area of 82,400 square kilometers, with 40 administrative districts (autonomous counties and cities) and 15 districts (Wanzhou District, Fuling District, Yuzhong District, dadukou district, Jiangbei District, Shapingba District, Jiulongpo District, Nan 'an District, Beibei District, Wansheng District, Shuangqiao District, Yubei District, Banan District, Qianjiang District and Changshou District). 4 county-level cities (Jiangjin, Hechuan, Yongchuan and Nanchuan); 2 1 county (autonomous county) (Qijiang, Tongnan, Tongliang, Dazu, Rongchang, Bishan, liangping county, Chengkou, Fengdu, Dianjiang, Wulong, Zhongxian, Kaixian, Yunyang, fengjie county, Wuxi, Shizhu Tujia Autonomous County, Xiushan.