The stone of the heart is the largest stone inscription in Putuo Mountain. It is located under the Xitianmen, about 300 square meters wide, round and smooth, and a huge "heart" word is engraved in the middle. This word is 5 meters long, 7 meters wide, and nearly 50 meters around. The center can accommodate eight or nine people. The whole word can accommodate nearly 100 people. It can be said that it is "big heart".