Chiang Mai, largest city in northern Thailand and the third largest city in the nation after metropolitan Bangkok and Nakhon Ratchasima. It is located on the Ping River, a major tributary of the Chao Phraya River, near the centre of a fertile intermontane basin at an elevation of 335 m. It serves as the religious, economic, cultural, educational, and transportation centre for both northern Thailand and part of neighbouring Myanmar (Burma). Once the capital of an independent kingdom, the city also has strong cultural ties with Laos.