Wiang Kum Kam
Tha Wang Tan, Thailand
Wiang Kum Kam (Northern ᩅ᩠ᨿᨦᨠᩩᨾᨠᩣ᩠ᨾ) is an historic settlement and archaeological site along the Ping River, which was built by King Mangrai the Great as his capital before he moved it to Chiang Mai. It was flooded and abandoned more than 700 years ago; that move became more understandable in 2005, when the ancient city was flooded three separate times as the river overflowed its banks in that area of Chiang Mai.
Archaeological site data from Wikidata (CC0). Summary from Wikipedia (CC BY-SA).