According to the Chinese Daoism, the lake was named during the Southern Dynasty when somebody noticed a black dragon water god that appeared in the form of a snake and turtle. Xuanwu Lake today has more than six miles of coastline and it spread on over 440 hectares.
The mountains surround the lake that has a total of five isles. The list of isles includes Ying Isle with blossoming cherry, Cui Isle that is famous for quietness, Huan Isle with willow trees, Ling Isle with golden and purple Clouds, and Liang Isle with many chrysanthemums. Xuanwu Lake is considered to be an important landscape of Nanjing and is protected by the state.