Interstate 685 North Carolina

Interstate 685 North Carolina


Interstate 685 is a proposed route overlaying the U.S. 421 corridor from I-95 near Dunn northwest to Sanford, Siler City and I-85 at Greensboro. Language in the Bipartisan Infrastructure Bill signed into law in November 2021 designated over 100 miles of U.S. 421 as a High Priority Corridor. This action allows the North Carolina Department of Transportation (NCDOT) to request a future Interstate designation from the Federal Highway Administration (FHWA).1

Route Information

  • North End – Greensboro, NC

  • South End – Sanford, NC

  • Mileage – 100

  • Cities – Greensboro, Siler City, Sanford

  • Junctions – I-85

Source: estimate


Proponents of I-685 in 2021, including area business and civic leaders in addition to local and state officials, envision economic growth possibilities in the Carolina Core region along the new corridor. The designation is also part of the Piedmont Triad Partnership’s long range strategic vision for the Carolina Core. The three year effort advocating for the future Interstate designation also cited improving access to Fort Liberty near Fayetteville as well as aiding in evacuation during natural disasters. Additionally seven counties along the route passed resolutions endorsing Future I-685.1

Planned development along the corridor includes the Greensboro-Randolph Megasite. Located along U.S. 421 in Randolph County, origins of the megasite go back to 2015 when the Greensboro-Randolph Megasite Foundation was formed. Together with Randolph County government and the North Carolina Railroad Company, land purchases commenced on the 1,800 acre site. Toyota announced the construction of a new $1 billion battery plant for the megasite in December 2021.2

The American Association of State Highway and Transportation Officials (AASHTO) approved the application for the establishment of Interstate 685 in North Carolina at the Route Numbering Committee 2022 Spring Meeting. The decision is contingent upon approval from the Federal Highway Administration (FHWA).

North End – I-85 US 421 – Greensboro, North Carolina

The north end of Interstate 685 is where U.S. 421 connects with Interstate 85 (Greensboro Urban Loop) at a directional cloverleaf interchange in southeastern Greensboro. U.S. 421 joins I-85 west from the exchange to I-73 north.

South End – US 1 US 421 – Sanford, North Carolina

U.S. 421 links with Interstate 95 on the east side of Dunn. As U.S. 421 runs across Dunn through Downtown, a new alignment for Interstate 685 will have to be planned around the city.


  1. “Infrastructure bill clears way for future I-685.” The Sanford Herald (NC), November 19, 2021
  2. “Key figure in developing megasite sees good things for Randolph County coming out of disappointment.” WGHP TV-8 (High Point, NC), April 11, 2022.

Page updated February 3, 2024.