At the northernmost area of the Temple of Heaven stands the hall, a round 38m tall palace with three-layer eaves. The hall is 32.72m in diameter. It is provided with blue glazed tiles on the roof and the whole structure is made of brick and wood. The Hall is the most magnificent building at the Temple of Heaven. It is believed to be the place closest to Heaven. Three layers of roof are covered with deep blue glazed tiles to symbolize the colour of the sky. Inside the hall stand 28 rare nanmu colomns, among which the inner 4 stand for four seasons, the middle 12 for 12 months, the outer 12 for 12 traditionally divided time units and constellations.