Sword Lake Octagon House stands behind the Ly Thai To statue in Ly Thai To Park beside Hoan Kiem Lake in Hanoi. It was built around 1901 during the French colonial period and hosts traditional music and art events and evening concerts. From early morning after 6 a.m., people dance or exercise to music, and children ride kick scooters and electric cars. When no event is scheduled, there is little to do.