Hoàn Kiếm Lake (Vietnamese: Hồ Hoàn Kiếm, chữ Hán: 湖還劍, meaning "Lake of the Returned Sword" or "Lake of the Restored Sword"), also known as Sword Lake (Hồ Gươm) or Tả Vọng Lake (Hồ Tả Vọng), is a fresh water lake, measuring some 12 ha in the historical center of Hanoi, the capital city of Vietnam.