The Thai Rigeback is an ancient breed of dog. The breed was formerly unknown outside of Thailand, but is gaining notice in the western world. The breed is still very rare outside of Thailand . The Thai Ridgeback is one of only three breeds that has a ridge of hair that runs along its back in the opposite direction to the rest of the coat (The others are Rhodesian Ridgeback and Phu Quoc Ridgeback). They are also known as a Mah Thai Lang Ahn.