The Williams River is a 27.0-mile (43.5 km) river in the U.S. state of Vermont. It is a tributary of the Connecticut River. Its watershed covers 117 square miles; land use is about 80% forested and 4% agricultural, and the upper river supports wild brook trout and brown trout. The river is a target for prospectors who can be seen panning for placer gold, south of the Town of Ludlow, near the site of the Rio Tinto open-pit talc mine.