Several special routes exist for U.S. Route 51.

Ponchatoula–Hammond business route

Dyersburg business route

South Fulton–Fulton bypass route

U.S. Route 51 Bypass (US 51 Byp.) was a

bypass Bypass may refer to: * Bypass (road), a road that avoids a built-up area (not to be confused with passing lane) * Flood bypass of a river Science and technology Medicine * Bypass surgery, a class of surgeries including for example: ** Heart bypas ...

of the downtown areas of South Fulton, Tennessee and Fulton, Kentucky. It was commissioned in 1970. In 1989, mainline US 51 and US 45 were moved to the bypass, and the bypass designation was decommissioned.

Decatur business route

U.S. Route 51 Business (US 51 Bus.) was a business loop that ran through downtown

Decatur, Illinois Decatur ( ) is the largest city and the county seat of Macon County in the U.S. state of Illinois, with a population of 70,522 as of the 2020 Census. The city was founded in 1829 and is situated along the Sangamon River and Lake Decatur in Ce ...

. It was commissioned in 1978, after a freeway bypass of Decatur was completed. In 1995, a freeway bypass of Elwin was completed, and US 51 Bus. was subsequently extended. In 2011, the route was decommissioned in an effort to reduce the amount of heavy truck traffic through downtown Decatur. Major intersections

Clinton business route

U.S. Route 51 Business (US 51 Bus.) is a business loop that runs through downtown Clinton, Illinois. It was commissioned in 1983, after an expressway bypass of Clinton was completed. Major intersections

Bloomington–Normal business route

Beloit spur route

Spur U.S. Highway 51 (Spur US 51) is an unsigned

spur route A spur route is a short road forming a branch from a longer, more important road such as a freeway, Interstate Highway, or motorway. A bypass or beltway should not be considered a true spur route as it typically reconnects with another or the s ...

, connecting US 51 with

WIS 213 State Trunk Highway 213 (often called Highway 213, STH-213 or WIS 213) is a state highway in the U.S. state of Wisconsin. It runs north–south in south central Wisconsin from Beloit to Evansville. History WIS 213 was design ...

via Broad Street in downtown Beloit, Wisconsin.

Plover–Stevens Point business route

Business U.S. Highway 51 (Bus. US 51) was a business loop that ran through the communities of Plover, Whiting, and Stevens Point. The route was commissioned after a freeway bypass of the Stevens Point area was completed in 1971. Around 2009, the route through Stevens Point was removed from the

Wisconsin State Trunk Highway System The Wisconsin State Trunk Highway System is the state highway system of the U.S. state of Wisconsin, including Wisconsin's segments of the Interstate Highway System and the United States Numbered Highway System, in addition to its other state tru ...

and became a city street, though the highway remained signed. In 2019, the American Association of State Highway and Transportation Officials approved eliminating Bus. US 51 as the remainder of the route was planned to be transferred to the villages of Plover and Whiting in 2020. Major intersections

Rothschild–Wausau business route

Business U.S. Highway 51 (Bus. US 51) is a business loop serving the communities of

Rothschild Rothschild () is a name derived from the German ''zum rothen Schild'' (with the old spelling "th"), meaning "with the red sign", in reference to the houses where these family members lived or had lived. At the time, houses were designated by signs ...

, Schofield, and Wausau, Wisconsin. It was commissioned in 1963, when an expressway bypass of the Wausau area was finished.

Merrill business route

Business U.S. Highway 51 (Bus. US 51) was a business loop that served Merrill, Wisconsin. The business loop was established in 1976 after a freeway bypass was completed east of Merrill. In 1998, without any significant changes during its existence, it was then decommissioned in favor of CTH-K and CTH-Q.

References

{{reflist 51 U.S. Route 51