U.S. Route 21

U.S. Route 21
US 21 highlighted in red
Route information
Maintained by SCDOT, NCDOT, and VDOT
Length	393 mi[1] (632 km)
Existed	November 11, 1926 (1926-11-11)[2]–present
Tourist routes	McTeer Bridge Scenic Byway US 21 Scenic Byway
Major junctions
South end	Hunting Island State Park, SC
Major intersections	I-95 near Yemassee, SC I-26 (three times in SC) I-20 in Columbia, SC I-77 (numerous times in SC/NC) I-85 in Charlotte, NC I-40 in Statesville, NC
North end	I-81 / US 52 in Wytheville, VA
Location
Country	United States
States	South Carolina, North Carolina, Virginia
Counties	SC: Beaufort, Hampton, Colleton, Bamberg, Orangeburg, Calhoun, Lexington, Richland, Fairfield, Chester, York NC: Mecklenburg, Iredell, Yadkin, Surry, Wilkes, Alleghany VA: Grayson, Wythe
Highway system
United States Numbered Highway System List Special Divided
South Carolina State Highway System Interstate US State Scenic
North Carolina Highway System Interstate US State Scenic
Virginia Routes Interstate US Primary Secondary Byways History HOT lanes
← US 20 US → US 22 ← SC 20 SC → SC 22 ← NC 20 NC → NC 22 ← SR 20 VA → SR 22

U.S. Route 21 or U.S. Highway 21 (US 21) is a north–south United States Numbered Highway, spanning 393 miles (632 km) from Hunting Island State Park, South Carolina, to Wytheville, Virginia. The route traverses three states, South Carolina, North Carolina, and Virginia. It connects southeastern cities, including Columbia, South Carolina, and Charlotte, North Carolina.

US 21 starts at Hunting Island State Park, bypasses Beaufort, South Carolina, and then heads north across the low country, paralleling Interstate 77 (I-77) through urban and rural areas before entering North Carolina. In North Carolina, US 21 frequently merges with and splits from I-77. The route enters Virginia, passing through hilly terrain before ending at the intersection of Interstate 81 (I-81) / U.S. Route 52 (US 52) in Wytheville.

Despite the "1" indicating that it is a major north–south highway, US 21 only travels through three states and is no longer a cross-country route, as many sections have been replaced by I-77 in Ohio and West Virginia. Historically, US 21 was longer before the Interstate Highway System was established. US 21 originally ran from Cleveland, Ohio, to Yemassee, South Carolina, it was later extended to Beaufort and Hunting Island State Park. Over time, its length was reduced, making it the second-shortest major north–south route after U.S. Route 91 (US 91).

US 21 serves as an alternative to the more heavily trafficked interstates in the area, particularly I-77, I-26, and Interstate 95 (I-95).