U.S. Route 310 is a spur of U.S. Route 10

U.S. Route 10

U.S. Route 10 is an east–west United States highway formed in 1926. Though it never became the cross-country highway suggested by the "0" as the last digit of its route number, U.S...

. It runs for 108 miles (173.8 km) from Laurel, Montana

Laurel, Montana

Laurel is a city in Yellowstone County, Montana, United States. It is part of the Billings, Montana Metropolitan Statistical Area, and is located in the Yellowstone Valley, as an east-west terminal division point of the Burlington-Northern Railroad.. The population was 6,781 at the 2010 census.Both...

 to Greybull, Wyoming

Greybull, Wyoming

Greybull is a town in Big Horn County, Wyoming, United States. The population was 1,815 at the 2000 census.-Geography:Greybull is located at ....

. It passes through the states of Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

 and Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

. Near the town of Lovell, Wyoming

Lovell, Wyoming

Lovell is a town in Big Horn County, Wyoming, United States. The population was 2,281 at the 2000 census.-Geography:Lovell is located at ....

, US 310 is concurrent with U.S. Route 14A for approximately three miles.

Historically, U.S. 310 intersected with U.S. Route 10 at Laurel

Laurel, Montana

Laurel is a city in Yellowstone County, Montana, United States. It is part of the Billings, Montana Metropolitan Statistical Area, and is located in the Yellowstone Valley, as an east-west terminal division point of the Burlington-Northern Railroad.. The population was 6,781 at the 2010 census.Both...

. After 1986, when U.S. 10 was decommissioned west of West Fargo, North Dakota

West Fargo, North Dakota

As of the census of 2000, there were 14,940 people, 5,771 households, and 4,091 families residing in the city, however the current population of West Fargo is estimated at over 26,000 residents. The population density was 2,049.2 per square mile . There were 5,968 housing units at an average...

, U.S. Route 310 no longer connected to its "parent" route.