Hoàn Kiếm is one of the four original urban districts of Hanoi, the capital city of Vietnam. It is named after the scenic Hoàn Kiếm Lake. The lak…Hoàn Kiếm is one of the four original urban districts of Hanoi, the capital city of Vietnam. It is named after the scenic Hoàn Kiếm Lake. The lake is in the heart of the district and serves as the focal point of the city's public life. The majority of tourist attractions in Hanoi are also located in the district.