U.S. Route 421 in North Carolina

U.S. Highway 421
US 421 highlighted in red
Route information
Auxiliary route of US 21
Maintained by NCDOT
Length	328 mi[1] (528 km)
Existed	1931–present
Major junctions
South end	NC 211 / Fort Fisher-Southport Ferry at Fort Fisher
Major intersections	I-140 near Wilmington US 701 in Clinton I-95 in Dunn US 1 / US 15 / US 501 / NC 87 in Sanford US 64 in Siler City I-85 near Pleasant Garden I-73 / US 220 in Greensboro I-40 / I-840 in Greensboro US 52 / NC 8 in Winston-Salem I-77 near Brooks Crossroads
North end	US 421 / SR 34 at the Tennessee line
Location
Country	United States
State	North Carolina
Counties	New Hanover, Brunswick, Pender, Sampson, Duplin, Harnett, Lee, Chatham, Randolph, Guilford, Forsyth, Yadkin, Wilkes, Watauga
Highway system
United States Numbered Highway System List Special Divided North Carolina Highway System Interstate US State Scenic
← NC 417 → I-440

U.S. Route 421 (US 421) is part of the United States Numbered Highway System that runs from Fort Fisher, North Carolina to Michigan City, Indiana. In the U.S. state of North Carolina, US 421 travels 328 miles (528 km) from its southern terminus at Fort Fisher to the Tennessee state line near the community of Zionville, North Carolina. US 421 traverses the state from east to west travelling from the coastal plains to Appalachian Mountains. It provides an important connection between the cities of Wilmington, Sanford, Greensboro, Winston-Salem, and Boone. Despite being signed as north–south, much of the routing of US 421 in North Carolina runs in an east–west direction, particularly between Greensboro and the Tennessee state line. Portions of US 421 have been upgraded to freeway standards including the majority of its routing between Sanford and North Wilkesboro.

US 421 was established in 1931 between Greensboro and Boone, North Carolina replacing North Carolina Highway 60 (NC 60). In 1932, the highway was extended northwest through Sugar Grove to Mountain City, Tennessee, and southeast along NC 60 to Wilmington. US 421 was extended south from Wilmington to Fort Fisher in 1936, replacing NC 40. Since 1936, the highway has been upgraded and readjusted throughout North Carolina.

A majority of the highway is part of the North Carolina Strategic Highway Corridors system.^[2] Because of this designation, the state has made numerous changes converting a rural two-lane highway into a major freeway/expressway with 4 or more lanes. Numerous former segments of the highway named "Old U.S. Route 421" are found along the entire route.