According to historical records, in the 19th year of Tang Zhenguan (645), Xuanzang returned from India, bringing back a large number of Buddhist relics, hundreds of Sanskrit scriptures and eight gold and silver Buddha statues. With the approval of the imperial court, Xuanzang personally presided over the construction of the Big Wild Goose Pagoda in order to worship and treasure the Buddhist scriptures, gold and silver Buddha statues, relics and other treasures brought back. But until now, no one knows where the treasure Xuanzang brought back is.
Wang Yarong thought there was a dungeon under the ancient pagoda. Just as there is a dungeon under the Famen Temple pagoda, there must be a dungeon under the Big Wild Goose Pagoda, but it has not been excavated yet. It is speculated that the underground palace under the Big Wild Goose Pagoda is likely to contain Buddhist treasures that Xuanzang brought back at the beginning.
Xie Shoutao, director of the Xi Wild Goose Pagoda Storage Center, said that in 2007, the relevant departments had detected the internal structure of the Wild Goose Pagoda, and the ground penetrating radar had detected a hole in the underground of the Wild Goose Pagoda, which should be the underground palace of the Wild Goose Pagoda.