State Route 3 (Tennessee)

U.S. Route 51
State Route 3
Route information
Maintained by TDOT
Length	135.90 mi (218.71 km)
Major junctions
South end	US 51 at the MS line
	I-55 in Memphis US 78 in Memphis US 64 / US 70 / US 72 / US 79 in Memphis I-240 in Memphis I-40 in Memphis Future I-69 / SR 300 in Memphis Future I-269 / SR 385 in Millington I-155 / US 412 in Dyersburg Future I-169 / US 45W / SR 22 near Union City US 45 / US 45E in South Fulton
North end	US 51 / Purchase Parkway at the KY line
Location
Counties	Shelby, Tipton, Lauderdale, Dyer, Obion
Highway system
United States Numbered Highway System List Special Divided Replaced Tennessee State Routes Interstate US State ← SR 2 SR 3 SR 4 → ← SR 50 US 51 SR 51 →

U.S. Route 51 (US 51), mostly overlapped by the unsigned State Route 3 (SR 3), is a north–south state highway in the U.S. state of Tennessee, that is 135.9 miles (218.71 km) long. It begins in Shelby County and ends in Obion County. The SR 3 designation is seen largely on mileposts.

The two places where US 51 and SR 3 differ are in Memphis, where US 51 has been moved to Danny Thomas Boulevard (State Route 1 / State Route 4), while SR 3 remains on the one-way pair of 2nd and 3rd Streets, and in South Fulton, where US 51 crosses the state line on State Route 215 to the Purchase Parkway, while SR 3 remains on the old road, now U.S. Route 45.

US 51 enters Tennessee at Memphis and runs north through the cities of Millington, Munford, Atoka, Brighton, Covington, Henning, Ripley, Halls, Dyersburg, Troy, Union City, and South Fulton.

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Wikipedia