To the northeast of Doumu Palace, about 400 meters away, is the well-known scenic spot Sutra Rock Valley. On the level surface of a huge stone which covers an area of more than 2,000 square meters, engraved a quotation from the Buddhist Scripture Vajracchedikasutra, and each character is 35 to 50 centimeters wide. There were 2799 characters originally, but eroded by rain and wind or destroyed by natural disasters, only 1067 characters exist nowadays. It is one of the largest sutra rock inscriptions in China and has been highly praised by the calligraphers of successive dynasties. An argument on when the big characters were engraved never ceased. Guo Moruo firmly believed that they were engraved in the North Qi Dynasty and has existed for more than 1,400 years. There are other inscriptions around the sutra rock inscription.