Neun Dhamma Sala is situated at Dhamma Sala temple, 6 km to the east of Phra Pathom Chedi. The structure of Neun Dhamma Sala looks resemble a hill. Many valuable treasures were hidden under the ground, such as ancient pottery, which may not be taken out because legend has it that there is a treasure guardian spirit watching over them.
There is an opening tunnel, which is believed to connect Wat Dhamma Sala to Wat Phra Mayn.