Let's swing our oars, the boat pushes aside the waves, the sea reflects the beautiful white tower, surrounded by green trees and red walls, the boat gently drifts in the water, and the cool wind blows in front of us... This well-known old song describes Beijing Beihai Park. Beihai Park was originally built in Liao, Jin and Yuan Dynasty. Ming and Qing Dynasties were imperial gardens. It is one of the oldest, most complete, most comprehensive and representative imperial gardens in China. It is also the longest and most complete imperial gardens in China.