The Temple Mound is located at Wat Thammasala, about 6 kilometers east of the Phra Pathom Chedi, on the south side of the Phetkasem Road. It is another ancient site that resembles the temple mound at Wat Phra Meru before excavation was carried out. This mound has not been excavated like the one at Wat Phra Ngam due to the existing structures at its front, and it currently serves as the site of Thammasala.