Georgia State Route 407

Interstate 285
The Perimeter
Route information
Maintained by GDOT
Length:	63.98 mi (102.97 km)
Existed:	1963 – present
Major junctions
Beltway around Atlanta
	SR 154 / SR 166 near East Point I‑20 in Atlanta I‑75 near Smyrna US 19 / SR 400 in Sandy Springs I‑85 near Doraville US 78 / SR 410 near Clarkston I‑20 near Panthersville I‑675 near Conley I‑75 near Forest Park I‑85 / SR 14 near College Park
Location
Counties:	Clayton, Fulton, Cobb, Dekalb
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Georgia State Routes Interstate U.S. State ← SR 284 SR 285 → ← SR 406 SR 408 →

Interstate 285 (I-285) is an Interstate Highway loop encircling Atlanta, Georgia, for 63.98 miles (102.97 km). I-285 also carries unsigned State Route 407 (SR 407), and is colloquially referred to as The Perimeter. Suburban sprawl has made it one of the most heavily-traveled roadways in the United States, and portions of the highway slow, sometimes to a crawl, during rush hour. It is also signed as Atlanta Bypass on I-75/I-85.

It is estimated that more than two million people use the highway each day, making it the busiest Interstate in the Atlanta metropolitan area.

I-285 is eight to 12 lanes wide, with the northern part from I-75 to SR 400 to I-85 the most heavily traveled. One segment of the highway near Spaghetti Junction (a large, flyover highway interchange northeast of Atlanta) with I-85 widens to 18 lanes, including collector-distributor lanes. Exits are numbered clockwise, starting at the southwestern-most point at I-85, and ending just east of there where it meets I-85 again near Hartsfield–Jackson Atlanta International Airport.

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Wikipedia