The Hall of Prayer for Good Harvests at the Temple of Heaven. When Emperor Yongle built the Forbidden City in 1406, he also envisioned this remarkable temple and park to the south of the City. This circular wooden hall, capped with a golden ball, is a shining emblem of China's imperial architecture. The entire temple was constructed without a single nail and the pieces artfully fitted into place without cross beams. Four massive pillars, known as the Dragon Well Pillars, bear much of the weight, with help from 28 lesser pillars. This temple was destroyed in 1889 by lightning and recreated in recent years to what you see here. Visitors are not allowed inside.