The temple is enclosed by a long wall

Covering an area of 2,700,000 square meters (3,529,412 square yards), it is larger than the Forbidden City. As the 'Sons of Heaven’, Chinese emperors were precluded from building a dwelling for themselves that was greater than the earthly residence dedicated to Heaven hence the difference in overall size of the two complexes. The temple is enclosed by a long wall. The northern part within the wall is semicircular symbolizing the heavens and the southern part is square symbolizing the earth. The northern part is higher than the southern part. This design shows that the heaven is high and the earth is low and the design reflected an ancient Chinese thought of 'the heaven is round and the earth is square'.