The Minidoka Dam is an earthfill dam on the Snake River in south central Idaho. The dam, originally completed in 1906, is east of Rupert on county highway 400; it is 86 feet (26 m) high and nearly a mile (1.6 km) in length, with a 2,400-foot (730 m) wide overflow spillway section. The dam and power plant were listed on the National Register of Historic Places in 1974. Walcott Park, close to the dam, is a popular summertime picnic area.