South Carolina Highway 641

South Carolina Highway 641 (SC 641) is a 21.560 mi primary state highway in the U.S. state of South Carolina. It provides the city of Allendale with a direct route toward Charleston, via SC 64 and U.S. Route 17 (US 17). It also serves access to Rivers Bridge State Park.

History
The highway was established around 1932 as a new primary spur of SC 64 to SC 36 (today US 601). By 1938, SC 641 was extended west on new routing to SC 33/SC 331 (today US 321) in Sycamore. In 1942, its alignment was straightened, leaving Rivers Bridge Road (S-5-31/S-15-37). By 1948, SC 641 was extended west to Allendale, replacing part of SC 73. In 1952, it was extended west again to the southern boundary of the Savannah River Plant, replacing part of SC 28; reaching its apex of over 44 mi long. Between 1968 and 1970, SC 641 was truncated at US 301, its former route replaced by SC 125.