Ancient Chinese believed that the sky was round and the earth was square，therefore the two shapes were frequently used in the temple Its inner and outer walls，for instance， are round above but square below. The three tiers of Circular Mound are round，but its two outer walls are low and circular inside while square outside. Hall of Prayer for Good Harvest and its base are round，but its surrounding wall is square. Such format is not hard to find elsewhere in the temple.
Moreover，the number‘9”and its multiples are repeatedly encountered in the temple. Hall of Prayers for Good Harvest is related with agriculture，therefore the numbers found here are connected with farming:“4”for the year seasons,"12"for the months and“24" for the solar terms.