I’d spotted it online—the area around Ban Tha Song
Ban Tha Song Yang or just Tha Song Yang? Two separate villages on the same Route 105. Since "ban" is just a prefix meaning "village," you could say both have the exact same name—so much so that even cartographers often mix them up, merging them into one spot despite the ~50 km between them (same thing on Google Earth).
Both sit along the Moei River, which forms the border with Myanmar in this area.
Tha Song Yang: the southernmost of the two, about 2 hours by songthaew north of Mae Sot. A really peaceful, pleasant spot with hang yao service for locals crossing between the two countries. A few places to stay (including a decent hotel), some street food stalls, a market, and a 7-Eleven.
Transport: six daily songthaews covering the full Mae Sot–Mae Sariang route, plus a songthaew every 20 minutes from Mae Sot to Tha Song Yang.
Ban Tha Song Yang: about 50 km farther north. Also peaceful and quiet, with a steady flow of hang yaos shuttling locals between the two countries. Thai is barely spoken here, and English isn’t at all—Karen is the dominant language. A few food stalls and a small market for meals, but no accommodations (so a soup vendor let me sleep in her shop after bringing me a mat, mosquito net, fan, and a multi-dish meal from her home).
Transport: the same six daily songthaews that run the full Mae Sot–Mae Sariang route.
Myanmar as seen from Tha Song Yang:
