Hoan Kiem Lake or Sword Lake is a natural freshwater lake in the heart of Hanoi capital. Previously, Hoan Kiem Lake was also called Luc Thuy Lake due to its green water in four seasons all year round, or another name is Thuy Quan Lake - Sailor Lake. Around the 15th century, it was renamed Hoan Kiem Lake (returning the sword) associated with the legend of King Le Thai To returning the magic sword to the magic turtle. This lake is the intersection between famous old neighborhoods such as: Hang Dao Street, Luong Van Can Street, Hang Ngang Street,... with the Western neighborhoods planned by the French more than 100 years ago: Trang Thi, Trang Tien, Dinh Tien Hoang, Ba Trieu, Hang Bai,...