Time in South Dakota Time in South Dakota South Dakota lies in both the Mountain Time Zone and the Central Time Zone. Mountain Time roughly contains the western half of the state, but not all of it. Rapid City is the largest city in the Mountain Time portion of the state. Central Time contains the eastern half of the state and roughly more of the state than the Mountain Time Zone and includes the state capital Pierre and the largest city, Sioux Falls. The 2 zones for South Dakota as given by zone.tab of the IANA time zone database. Columns marked * are from
South Dakota Highway 71 South Dakota Highway 71 South Dakota Highway 71 (SD 71) is a state highway in the southwestern part of the U.S. state of South Dakota. It travels from the Nebraska state line, where it continues as N-2/N-71, through the Black Hills National Forest, to U.S. Route 18 Bypass (US 18 Byp.) in Hot Springs. The road was originally a part of SD 87. It became SD 71 in 1962. SD 71's southern terminus is at the Nebraska border in Black Hills National Forest where it has the same number. In the forest, the route meets the terminus of South Dakota