Interstate 15 Business (Great Falls, Montana)

Interstate 15 Business (I-15 Bus.) is a business loop of Interstate 15 (I-15) in Cascade County, Montana, United States, almost entirely within Great Falls. The route links I-15 (which bypasses downtown Great Falls to the west) with the center of Great Falls. As its business loop designation implies, I-15 Bus. terminates at I-15 (running concurrently with US Highway 89, or US 89, and Montana Highway 200, or MT 200, through western Great Falls) at each end. The southernmost 0.83 miles (1.34 km)^[1] of the route from the interchange with I-15 to Fox Farm Road is designated, but not signed, as Interstate 315 (I-315).^[2] I-315 is the second shortest Interstate in the country; only the unsigned I-878 in New York is shorter; it is also the northernmost auxiliary Interstate of I-15.

Interstate 15 Business
I-15 Bus. highlighted in red and unsigned I-315 highlighted in blue
Route information
Business route of I-15
Maintained by MDT
Length	5.834 mi[citation needed] (9.389 km)
Existed	1967–present
Major junctions
South end	I-15 / US 89 / MT 3 / MT 200 south of Great Falls
Major intersections	US 89 / MT 3 / MT 200 in Great Falls
North end	I-15 / US 89 / MT 200 in Great Falls
Location
Country	United States
State	Montana
Counties	Cascade
Highway system
Interstate Highway System Main Auxiliary Suffixed Business Future Montana Highway System Interstate US State Secondary
← US 312 I-315 → S-315

Route description

First Baptist Church, in the city center on 2nd Avenue, March 2013

I-15 Bus. begins at I-15 exit 278 in an unincorporated area of Cascade County, a short distance southwest of Great Falls. At the trumpet interchange, US 89 and MT 200 separate from I-15 and merge with I-15 Bus. Additionally, MT 3 begins at the interchange and follows the three routes to the east. Just east of the interchange with I-15, I-15 Bus. intersects 14th Street. The Interstate Highway standard conditions come to an end a short distance to the east at an intersection with Fox Farm Road.^[3] Here, the 0.83-mile (1.34 km)^[1] I-315 (designated along I-15 Bus. from I-15 to Fox Farm Road) comes to an end^[4] while I-15 Bus., US 89, MT 3, and MT 200 continue across the Missouri River into downtown Great Falls.^[3]

Within downtown, the four routes remain concurrent along 10th Avenue South to the parallel one-way couplet of 5th and 6th streets. I-15 Bus. northbound separates from US 89/MT 3/MT 200 at 6th Street, following the street northward through the city to the one-way 2nd Avenue North near the city center. I-15 Bus. turns to the west, following 2nd Avenue North to Park Street, then Park Street south to Central Avenue, where I-15 Bus. northbound rejoins the routing of I-15 Bus. southbound. Between Central Avenue and 10th Avenue South, I-15 Bus. southbound is routed along 1st Avenue North east to 5th Street South, then 5th Street South to 10th Avenue.^[3]

I-15 Bus. follows Central Avenue to the west, crossing the Missouri River once more as it exits downtown. After several intersections with local streets, I-15 Bus. terminates at I-15 exit 280. Central Avenue, however, continues westward from the exit.^[3]

History

Major intersections

The entire route is in Cascade County.

Location	mi	km	Exit	Destinations	Notes
​	0.000	0.000	—	I-15 / US 89 north / MT 200 west / MT 3 begins – Helena, Shelby	Western end of I-315/US 89/MT 3/MT 200 concurrency; I-15 exit 278
Great Falls	0.335	0.539	0	14th Street Southwest	Interchange
	0.828	1.333	—	Fox Farm Road, 6th Street Southwest	Eastern end of I-315 concurrency
	2.341	3.767		US 89 south / MT 3 south / MT 200 east (10th Avenue South) to US 87	Eastern end of US 89/MT 3/MT 200 concurrency; I-15 Bus. becomes 6th Street South (one-way street)
	5.834	9.389		I-15 / US 89 / MT 200 – Helena, Shelby	Northern terminus; I-15 exit 280
1.000 mi = 1.609 km; 1.000 km = 0.621 mi       Concurrency terminus

See also

• U.S. Roads portal
• Montana portal

• Business routes of Interstate 15 in Montana

References

1. Starks, Edward (January 27, 2022). "Table 2: Auxiliary Routes of the Dwight D. Eisenhower National System of Interstate and Defense Highways". FHWA Route Log and Finder List. Federal Highway Administration. Retrieved April 9, 2023.
2. "Interstate 315 Montana". Interstate-Guide.com. Retrieved September 24, 2007.^{[self-published source]} (has pictures showing that I-315 is signed as BL 15)
3. Rand McNally (2007). "Montana" (Map). The Road Atlas '07. Chicago: Rand McNally. p. 61. § M16, N16.
4. Montana Department of Transportation (2001). Great Falls - Cascade County (PDF) (Map). Helena: Montana Department of Transportation. Retrieved September 24, 2007.

External links

Template:Attached KML/Interstate 15 Business (Great Falls, Montana)

KML is from Wikidata

• Media related to Interstate 15 Business (Great Falls, Montana) at Wikimedia Commons