This complex of Taoist religious buildings was constructed in the early 15th century under the Yongle Emperor, who also commissioned the Forbidden City, just to the north. The temple's central building is the Hall of Prayer for Good Harvests, a 38-meter-high (125-foot-high), three-tiered structure atop a three-tiered marble base. The wooden hall was built entirely without nails. Inside, the beautifully painted walls and ceiling make it a riot of color. Don't forget to explore the surrounding park, where elderly Chinese gather to sing, dance, and play traditional instruments.