Located in the village of Tham Lot, approximately 77 kilometers from the town of Mae Hong Son, this area is an important archaeological site managed by the Pai River Wildlife Sanctuary. One of the main attractions here is the "Tham Nam Lod" cave, where the Nam Lang stream flows through the mountains and emerges on the other side, forming a cave adorned with stunning stalactites and stalagmites. Archaeological findings in the cave suggest it has been inhabited for around 2,000 years. The cave stretches about 1 kilometer in length and features three large chambers, each with its own name. The first is the "Tham Sao Hin Luang," a vast cave filled with beautiful stalactites and stalagmites. Its most striking feature is a colossal limestone pillar, created from multiple stalagmites, some reaching heights of up to 20 meters. Next is the "Tham Tukta," known for its small, nodular stalagmites that resemble dolls, alongside ancient wall paintings from prehistoric times, notable for their use of red and black colors—an uncommon sight in Thailand. The final cave on the tour route, found near the exit, is the "Tham Phi Man." In addition to its scenic stalactites and stalagmites, this cave has yielded fragments of pottery, seeds, stone tools, human teeth, and bones, as well as the enigmatic "Phi Man coffin." This coffin consists of a hollowed-out wooden log resembling a boat or a trough used for feeding animals. They come in various sizes, with larger ones placed on beams supported by 4 to 6 wooden posts set against the cave floor, each pair of posts drilled with holes for the beams that support the coffins. The Nature and Wildlife Study Center of Tham Nam Lod is open daily from 8:00 AM to 5:00 PM. Due to the cave's extreme darkness, self-guided exploration is not permitted. Visitors must hire a guide, who provides a torch, for a fee of 150 baht per person. The cave tour is divided into two sections: the first focuses on the two major caves—Tham Sao Hin Luang and Tham Tukta—while the second showcases Tham Phi Man. For accommodation and amenities, there are lodges available at the visitor center, and camping is permitted. For more details, visitors can directly contact the service unit at the Nature and Wildlife Study Center of Tham Nam Lod by calling 0 5361 7218.