The Chi River is the longest river in Thailand (765 km). It originates in the Phetchabun
mountains, Chiyaphum province and flows through the central part of the north-eastern region of
Thailand, passing Khonkaen, Mahasarakham, Kalasin, Roi-et and Yasothon, and then merges with
Mun River in Warinchamrab district, Ubon Ratchathani province before joining the Mekong River.
People living along the Chi River use it for domestic, agricultural, transport, industrial and, most
important, fishery purposes. Local fishermen have a long development in fisheries. Importantly, the
Chi River is known as one of the most important fishery resources in the north-eastern region. Fish