If you want a clear aerial view of the Forbidden City, you'll find it here. The park's central hill was created using earth left over from the digging of the imperial moat and was the highest point in the city during the Ming dynasty. It was designed to enhance the feng shui of the Forbidden City, by blocking the harsh northern wind and by burying a Mongol Yuan dynasty pavilion, the Yanchun Ge. In something of a riposte to the Chinese Ming dynasty, the Manchu Qianlong emperor built a tower by the same name (albeit in a very different style) in the Jianfu Gong Huayuan, within the Forbidden City. A tree on the east side of the hill marks the spot where the last Ming emperor, Chongzhen, supposedly hanged himself in 1644, just before Manchu and rebel armies overran the city. The original tree, derided as the "guilty sophora" during the Qing, was hacked down by Red Guards who failed to recognize a fellow anti-imperialist.