Wat Tham Thong Phannara is in Moo 9, Tambon Tham Phannara, about 2 kilometres from the Asia Highway (Highway No. 41) at the 192-193 km. marker, and about 1 kilometre from the district office. Legend has it that two nuns, named Pring and Prang, came by sea with many followers and valuable belongings for use in the building of a pagoda to entomb Lord Buddha’s relics. However, when they arrived at the port (Ban Pak Ra now), they found that the pagoda had already been completed, so they chose another suitable site to build, which was Thong cave.

They then built a reclining Buddha image in the cave. When the nuns died, their descendents placed their bones in the 2 Buddha images that they built. Since then, it became a tradition that on the first night with a full moon of the 11th lunar month (October), people would pay homage to the reclining image and the images representing the nuns called Phra Pring and Phra Prang. This Khun Tham ceremony is attended by a great number of worshippers who bring with them desserts for offerings and who come to tour the caves that consist of both dark and brightly lit caves.