Georgia State Route 500

State Route 500
Outer Perimeter Highway Northern Arc
Route information
Maintained by GDOT
Length:	55 mi (89 km)
History:	proposed
Major junctions
West end:	I‑75 near Cartersville
	I‑575 near Canton SR 400 near Cumming I‑985 in Buford
East end:	I‑85 in Buford
Highway system
Georgia State Routes Interstate U.S. State ← SR 422 SR 515 →

The Outer Perimeter is a freeway originally planned to encircle Atlanta, in the U.S. state of Georgia about 20 to 25 miles (32 to 40 km) outside of Interstate 285, which is colloquially referred to as the Perimeter and is a point of reference for local travel outside Atlanta's city core.

The original plan of the highway was to have roughly gone through or near the communities of Cartersville, Canton, Cumming, Buford, Dacula, Loganville, Conyers, McDonough, Hampton, Newnan, Peachtree City, Villa Rica, and Dallas. The roadway was to have roughly paralleled State Route 20, which goes around three sides of Atlanta.

A later incarnation of the highway only encompassed what was termed the Northern Arc and included the portion of the original planned highway from Interstate 75 near Cartersville across to Interstate 85 near the Mall of Georgia in Buford. One proposal tied to this version would have reportedly limited exits to five major interchanges, at the freeways that crossed it: I-75; I-575; Georgia State Route 400; Interstate 985; and I-85.

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Wikipedia