Road Information

Interstate 15 in Montana    
Total Mileage in State: 397 miles
Northern End: At Canadian border
Southern End: At Idaho state line
Mileage covered in Photos: 397 miles
Counties covered in Photos: Toole, Pondera, Teton, Cascade, Lewis and Clark, Jefferson, Silver Bow, Madison, Beaverhead
Major Junctions in Photos: US 2, in Shelby
US 89, in Great Falls
US 12/287, in Helena
I-90, in Butte
Control Cities in Photos: Shelby, Great Falls, Helena, Butte, Dillon

Southbound

Sections:
  • Section 1: Canadian Border to Great Falls (Exit 280)
  • Section 2: Great Falls (Exit 280) to Helena (Exit 194)
  • Section 3: Helena (Exit 194) to Butte (Exit 127)
  • Section 4: Butte (Exit 127) to Dillon (Exit 63)
  • Section 5: Dillon (Exit 63) to Idaho Border

Section 1: Canadian Border to Great Falls (Exit 280)

   

Merging onto Interstate 15 South from Exit 397 in Sweet Grass, just south of the border of Alberta, Canada. The customs station is immediately north of Exit 397. (Photo taken 5/24/16).

Interstate 15 South reassurance shield. (Photo taken 5/24/16).

Montana welcome sign on Interstate 15 South. (Photo taken 5/24/16).

Speed limit signs on Interstate 15 South. The speed limits start out at 80 mph for cars and 65 mph for trucks. These are the standard speed limits on most rural Interstate highways in Montana. (Photo taken 5/24/16).

Mileage sign on Interstate 15 South. It's 7 miles to Sunburst, 34 miles to Shelby, and 116 miles to Great Falls. (Photo taken 5/24/16).

Interstate 15 South at mile marker 395. (Photo taken 5/24/16).

Interstate 15 South at Exit 394: Ranch Access (Photo taken 5/24/16).

Another set of speed limit signs south of Exit 394. The speed limits are 80 mph for cars and 65 mph for trucks. (Photo taken 5/24/16).

Interstate 15 South at mile marker 393. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 389 - 1 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 389: S-552 - Sunburst (Photo taken 5/24/16).

Interstate 15 is subject to dust storms for the next mile. (Photo taken 5/24/16).

Mileage sign on Interstate 15 South. It's 10 miles to Oilmont-Kevin, 26 miles to Shelby, and 108 miles to Great Falls. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 385 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 385: Swayze Rd (Photo taken 5/24/16).

Interstate 15 South at mile marker 381. (Photo taken 5/24/16).

Interstate 15 South at Exit 379: S-343 / S-215 - Kevin / Oilmont (Photo taken 5/24/16).

Interstate 15 South at mile marker 378. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 373 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 373: Potter Rd (Photo taken 5/24/16).

Interstate 15 South approaching Exit 369 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at the Weigh Station in Toole County. (Photo taken 5/24/16).

Take Exit 364 to BNSF Intermodal Hub. Take Exit 363 to Port of Shelby. (Photo taken 5/24/16).

Interstate 15 South at Exit 364: Interstate 15 Business Loop - Shelby (Photo taken 5/24/16).

Take Exit 363 to Glacier National Park. (Photo taken 5/24/16).

Take Exit 363 to Port of Shelby. (Photo taken 5/24/16).

Interstate 15 South at Exit 363: US 2 - Shelby / Cut Bank (Photo taken 5/24/16).

Interstate 15 South approaching Exit 358 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 358: Marias Valley Rd / Golf Course Rd (Photo taken 5/24/16).

Interstate 15 South traverses a 6% downgrade ahead, as this warning sign reads. (Photo taken 5/24/16).

Interstate 15 South at mile marker 358. (Photo taken 5/24/16).

Interstate 15 South at mile marker 357. (Photo taken 5/24/16).

Interstate 15 South entering Pondera County. (Photo taken 5/24/16).

Interstate 15 South at Exit 352: Bullhead Rd (Photo taken 5/24/16).

Take Exit 348 to Lake Frances Recreation Area. (Photo taken 5/24/16).

Interstate 15 South at Exit 348: MT 44 - Valier Rd (Photo taken 5/24/16).

Interstate 15 South at Exit 345: S-366 - Ledger Rd / Tiber Dam (Photo taken 5/24/16).

Interstate 15 South at Exit 339: Interstate 15 Business Loop - Conrad (Photo taken 5/24/16).

A Rest Area and Weigh Station also exist off Exit 339. (Photo taken 5/24/16).

Interstate 15 South at Exit 335: Midway Rd (Photo taken 5/24/16).

Interstate 15 South at mile marker 332. (Photo taken 5/24/16).

Interstate 15 South at Exit 328: S-365 - Brady (Photo taken 5/24/16).

Mileage sign on Interstate 15 south. It's 14 miles to Dutton, 37 miles to Vaughn Junction, and 46 miles to Great Falls. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 321 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 321: Collins Rd (Photo taken 5/24/16).

Interstate 15 South at the Rest Area in Pondera County at mile marker 319. (Photo taken 5/24/16).

Interstate 15 South at mile marker 315. (Photo taken 5/24/16).

Interstate 15 South at Exit 313: S-221 / S-379 - Dutton / Choteau (Photo taken 5/24/16).

Interstate 15 South at mile marker 311. (Photo taken 5/24/16).

Interstate 15 South at mile marker 305. (Photo taken 5/24/16).

Interstate 15 South at Exit 302: S-431 - Power (Photo taken 5/24/16).

Interstate 15 South entering Cascade County. (Photo taken 5/24/16).

Interstate 15 South at mile marker 300. (Photo taken 5/24/16).

Interstate 15 South at Exit 297: Gordon (Photo taken 5/24/16).

Interstate 15 South at mile marker 296. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 290 - 1 mile. (Photo taken 5/24/16).

Take Exit 290 to Vaughn. (Photo taken 5/24/16).

Interstate 15 South at Exit 290: US 89 North / MT 200 West - Missoula (Photo taken 5/24/16).

Interstate 15 South reassurance shield. (Photo taken 5/24/16).

Turnout / Parking Area on Interstate 15 South in Cascade County. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 286 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 286: Manchester (Photo taken 5/24/16).

Sign listing the distances to the three upcoming exits to Great Falls. (Photo taken 5/24/16).

Take Exit 280 to Lewis & Clark Interpretive Center and Giant Springs State Park. (Photo taken 5/24/16).

Take Exit 282 to the Fairgrounds and Arena. (Photo taken 5/24/16).

Approaching the Great Falls area, the speed limit decreases to 65 mph for all traffic. (Photo taken 5/24/16).

Interstate 15 South at Exit 282: To US 87 North - NW Bypass (Photo taken 5/24/16).

Interstate 15 South entering the Great Falls city limits. (Photo taken 5/24/16).

Take Exit 280 to City Center. (Photo taken 5/24/16).

Interstate 15 South at Exit 280: Interstate 15 Business Loop - Central Ave W (Photo taken 5/24/16).

Section 2: Great Falls (Exit 280) to Helena (Exit 194)

   

The speed limit remains 65 mph through the Great Falls area. (Photo taken 5/24/16).

Interstate 15 South crossing Sun River at mile marker 280. (Photo taken 5/24/16).

Take Exit 278 to US 87 South toward Malmstrom AFB. (Photo taken 5/24/16).

Also take Exit 278 to University of Great Falls. (Photo taken 5/24/16).

Take Exit 278 to Great Falls College as well. (Photo taken 5/24/16).

Interstate 15 South at Exit 278: US 89 South / MT 200 East - 10th Ave South (Photo taken 5/24/16).

Interstate 15 South reassurance shield. (Photo taken 5/24/16).

Interstate 15 South at Exit 277: International Airport (Photo taken 5/24/16).

Leaving Great Falls, this sign states that it is now 86 miles to Helena and that State Capitol. (Photo taken 5/24/16).

Leaving the Great Falls area, the standard rural speed limits of 80 mph for cars and 65 mph for trucks resume. (Photo taken 5/24/16).

Interstate 15 South at mile marker 273. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 270 - 1 mile. (Photo taken 5/24/16).

Take Exit 270 to First Peoples Buffalo Jump State Park. (Photo taken 5/24/16).

Interstate 15 South at Exit 270: S-330 - Ulm (Photo taken 5/24/16).

Mileage sign on Interstate 15 South. It's 13 miles to Cascade, 36 miles to Craig, and 78 miles to Helena. (Photo taken 5/24/16).

Interstate 15 South at mile marker 264. (Photo taken 5/24/16).

Interstate 15 South at mile marker 259. (Photo taken 5/24/16).

Interstate 15 South at Exit 256: MT 68 - Cascade (Photo taken 5/24/16).

Interstate 15 South at Exit 254: Cascade (Photo taken 5/24/16).

Mileage sign on Interstate 15 South. It's 10 miles to Canyon Access, 20 miles to Craig, and 62 miles to Helena. (Photo taken 5/24/16).

Interstate 15 South at mile marker 254. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 250 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at mile marker 251. (Photo taken 5/24/16).

Interstate 15 South at Exit 250: Local Access (Photo taken 5/24/16).

Interstate 15 South entering the Big Belt Mountains. Beautiful. (Photo taken 5/24/16).

Entering this mountainous stretch, the speed limit for cars decreases slightly to 75 mph. It remains 65 mph for trucks. (Photo taken 5/24/16).

Take Exit 247 ahead to Recreation Rd. (Photo taken 5/24/16).

Interstate 15 South at Exit 247: Hardy Creek (Photo taken 5/24/16).

View on Interstate 15 South in the Big Belt Mountains. (Photo taken 5/24/16).

Interstate 15 South crossing the Missouri River. (Photo taken 5/24/16).

Another gorgeous view on Interstate 15 South. (Photo taken 5/24/16).

Interstate 15 South at the Scenic View Area in Cascade County. (Photo taken 5/24/16).

Take Exit 244 to Recreation Rd. (Photo taken 5/24/16).

Interstate 15 South at Exit 244: Canyon Access (Photo taken 5/24/16).

View on Interstate 15 South as it prepares to pass under Novak Creek Ln off Exit 244. (Photo taken 5/24/16).

Interstate 15 South at mile marker 243. (Photo taken 5/24/16).

Interstate 15 South at mile marker 242. (Photo taken 5/24/16).

Interstate 15 South at Exit 240: Dearborn (Photo taken 5/24/16).

Interstate 15 South entering Lewis & Clark County. (Photo taken 5/24/16).

Interstate 15 South reassurance shield. (Photo taken 5/24/16).

The speed limits remain 75 mph for cars and 65 mph for trucks. (Photo taken 5/24/16).

Another view on Interstate 15 South. (Photo taken 5/24/16).

Interstate 15 South as it crosses the Missouri River a second time. (Photo taken 5/24/16).

Interstate 15 South at mile marker 236. (Photo taken 5/24/16).

Take Exit 234 to Recreation Rd and Holter Lake. (Photo taken 5/24/16).

Interstate 15 South at Exit 234: Craig (Photo taken 5/24/16).

Mileage sign on Interstate 15 South. It's 5 miles to the junction of US 287, 6 miles to Wolf Creek, and 41 miles to Helena. (Photo taken 5/24/16).

View on Interstate 15 South. (Photo taken 5/24/16).

Interstate 15 South at mile marker 231. (Photo taken 5/24/16).

Another view on Interstate 15 South. (Photo taken 5/24/16).

Interstate 15 South at Exit 228: US 287 North - Augusta / Choteau (Photo taken 5/24/16).

Watch for wildlife present on the roadway. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 226 - 1/4 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 226: S-434 - Wolf Creek (Photo taken 5/24/16).

View on Interstate 15 South. (Photo taken 5/24/16).

Parking Area on Interstate 15 South in Lewis & Clark County. (Photo taken 5/24/16).

Winding curves ahead. 50 mph around them is advised. (Photo taken 5/24/16).

Another view on Interstate 15 South. (Photo taken 5/24/16).

And another view on Interstate 15 South. (Photo taken 5/24/16).

And another. (Photo taken 5/24/16).

Interstate 15 South at mile marker 219. (Photo taken 5/24/16).

Interstate 15 South / US 287 South reassurance markers. (Photo taken 5/24/16).

View on Interstate 15 South. (Photo taken 5/24/16).

Another beautiful view on Interstate 15 South. (Photo taken 5/24/16).

View on Interstate 15 South. (Photo taken 5/24/16).

Interstate 15 South at mile marker 218. (Photo taken 5/24/16).

The speed limits remain 75 mph for cars and 65 mph for trucks. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 216 - 1/2 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 216: Sieben (Photo taken 5/24/16).

South of Exit 216, the standard rural speed limit of 80 mph for cars resumes while it remains 65 mph for trucks. (Photo taken 5/24/16).

Mileage sign on Interstate 15 South. It's 7 miles to Gates of the Mountains, 15 miles to Lincoln Road, and 24 miles to Helena. (Photo taken 5/24/16).

Interstate 15 South at mile marker 213. (Photo taken 5/24/16).

Interstate 15 South at mile marker 211. (Photo taken 5/24/16).

Interstate 15 South at Exit 209: Gates of the Mountains (Photo taken 5/24/16).

Interstate 15 South at mile marker 207. (Photo taken 5/24/16).

View on Interstate 15 South. (Photo taken 5/24/16).

Interstate 15 South at mile marker 204. (Photo taken 5/24/16).

Another view on Interstate 15 South. (Photo taken 5/24/16).

Weigh Station on Interstate 15 South in Lewis & Clark County. (Photo taken 5/24/16).

Interstate 15 South approaching Exit 200 - 1 mile. (Photo taken 5/24/16).

Interstate 15 South at Exit 200: S-279 / S-453 - Lincoln Rd (Photo taken 5/24/16).

Interstate 15 South at mile marker 199. (Photo taken 5/24/16).

Take any of the next 4 exits to Helena. (Photo taken 5/24/16).

Entering Helena, the speed limit once again decreases to 65 mph for all traffic. (Photo taken 5/24/16).

Interstate 15 South at Exit 194: Custer Ave (Photo taken 5/24/16).

Section 3: Helena (Exit 194) to Butte (Exit 127)

   

Take Exit 193 to Carroll College. (Photo taken 5/24/16).

Interstate 15 South at Exit 193: Interstate 15 Business Loop - Cedar St (Photo taken 5/24/16).

Take Exit 192 to the State History Museum. (Photo taken 5/24/16).

Also take Exit 192 to Helena College and University of Montana. (Photo taken 5/24/16).

Interstate 15 South at Exit 192: US 12 / US 287 South - Townsend / Capitol Area (Photo taken 5/24/16).

Interstate 15 South reassurance shield. (Photo taken 5/25/16).

Interstate 15 South at Exit 190: South Helena (Photo taken 5/25/16).

Interstate 15 South entering Jefferson County. (Photo taken 5/25/16).

Leaving Helena, the standard rural speed limit of 80 mph for cars resumes. It remains 65 mph for trucks as usual. (Photo taken 5/25/16).

Interstate 15 South at Exit 187: S-518 - Montana City (Photo taken 5/25/16).

Interstate 15 South reassurance shield. (Photo taken 5/25/16).

Mileage sign on Interstate 15 South. It's 5 miles to Clancy, 22 miles to Boulder, and 59 miles to Butte. (Photo taken 5/25/16).

Interstate 15 South at mile marker 184. (Photo taken 5/25/16).

Interstate 15 South at Exit 182: Clancy (Photo taken 5/25/16).

Speed Limits - 80 mph for cars, 65 mph for trucks. (Photo taken 5/25/16).

Mileage sign on Interstate 15 South. It's 5 miles to Jefferson City, 16 miles to Boulder, and 53 miles to Butte. (Photo taken 5/25/16).

Interstate 15 South at mile marker 179. (Photo taken 5/25/16).

Interstate 15 South at the Rest Area in Jefferson County. (Photo taken 5/25/16).

Interstate 15 South as it enters the Elkhorn Mountains. (Photo taken 5/25/16).

Interstate 15 South at Exit 176: Jefferson City (Photo taken 5/25/16).

Chain Up Area on Interstate 15 South, as it prepares to pass through the mountainous terrain of the Elkhorn Mountains. (Photo taken 5/25/16).

Interstate 15 South at mile marker 174. (Photo taken 5/25/16).

Interstate 15 South at mile marker 172. (Photo taken 5/25/16).

View on Interstate 15 South. (Photo taken 5/25/16).

Interstate 15 South at mile marker 170. (Photo taken 5/25/16).

Interstate 15 South at mile marker 169. (Photo taken 5/25/16).

Chain Removal Area on Interstate 15 South in the Elkhorn Mountains. (Photo taken 5/25/16).

Interstate 15 South at Exit 164: MT 69 - Boulder (Photo taken 5/25/16).

The speed limit decreases to 75 mph for cars through the Elkhorn Mountains. (Photo taken 5/25/16).

Mileage sign on Interstate 15 South. It's 7 miles to Basin, 16 miles to Bernice, and 36 miles to Butte. (Photo taken 5/25/16).

View on Interstate 15 South. (Photo taken 5/25/16).

Interstate 15 South at mile marker 163. (Photo taken 5/25/16).

Another view on Interstate 15 South. (Photo taken 5/25/16).

Interstate 15 South approaching Exit 160 - 1/2 mile. (Photo taken 5/25/16).

Interstate 15 South at Exit 160: High Ore Rd (Photo taken 5/25/16).

Interstate 15 South reassurance shield. (Photo taken 5/25/16).

Interstate 15 South at mile marker 159. (Photo taken 5/25/16).

Interstate 15 South at mile marker 158. (Photo taken 5/25/16).

Interstate 15 South at Exit 156: Basin (Photo taken 5/25/16).

The speed limits remain 75 mph for cars and 65 mph for trucks. (Photo taken 5/25/16).

More winding curves lie ahead. 55 mph is advised. (Photo taken 5/25/16).

Interstate 15 South entering Deerlodge National Forest. (Photo taken 5/25/16).

Interstate 15 South crossing the Boulder River. (Photo taken 5/25/16).

Interstate 15 South approaching Exit 151 - 1/2 mile. (Photo taken 5/25/16).

Interstate 15 South at Exit 151: Bernice (Photo taken 5/25/16).

Interstate 15 South at mile marker 151. (Photo taken 5/25/16).

Another Chain Up Area on Interstate 15 South, as it prepares to climb another grade. (Photo taken 5/25/16).

60 mph curve to the right ahead as Interstate 15 South begins to climb. (Photo taken 5/25/16).

View on Interstate 15 South continuing up the grade. (Photo taken 5/25/16).

Interstate 15 South at mile marker 146. (Photo taken 5/25/16).

Interstate 15 South at mile marker 145. (Photo taken 5/25/16).

More winding 60 mph curves ahead. (Photo taken 5/25/16).

Interstate 15 South at mile marker 144. (Photo taken 5/25/16).

At the top of the grade is another Chain Removal Area. (Photo taken 5/25/16).

Interstate 15 South at mile marker 143. (Photo taken 5/25/16).

Leaving the Elkhorn Mountains to the south, the standard rural speed limit of 80 mph for cars resumes. Still 65 mph for trucks. (Photo taken 5/25/16).

Interstate 15 South approaching Exit 138 - 1/2 mile. (Photo taken 5/25/16).

Take Exit 138 to Sheepshead Picnic Area. (Photo taken 5/25/16).

Interstate 15 South at Exit 138: Elk Park (Photo taken 5/25/16).

Watch for wildlife crossing the roadway. (Photo taken 5/25/16).

Interstate 15 South at Exit 134: Woodville (Photo taken 5/25/16).

Interstate 15 South entering Silver Bow County. (Photo taken 5/25/16).

Interstate 15 South as it crosses the Continental Divide at an elevation of 6,368 feet. (Photo taken 5/25/16).

At mile marker 133, this sign warns of a 6% downgrade ahead that lasts for 3 miles. The junction of Interstate 90 is at the bottom of the grade. (Photo taken 5/25/16).

Interstate 15 South entering the Butte-Silver Bow County Cultural Heritage Area. (Photo taken 5/25/16).

Interstate 15 South approaching the junction of Interstate 90 - 2 miles. (Photo taken 5/25/16).

View on Interstate 15 South as it descends into Butte. (Photo taken 5/25/16).

Interstate 15 South approaching Exit 129 - 1 mile. (Photo taken 5/25/16).

Scenic Overlook Area on Interstate 15 South approaching Butte. (Photo taken 5/25/16).

Approaching Butte and the junction of Interstate 90, the speed limit decreases to 65 mph for all traffic. Get in the left lane for Exit 129 to Interstate 90 East. Stay in the right lane for Interstate 90 West and to remain on Interstate 15 South. (Photo taken 5/25/16).

Interstate 15 South at Exit 129: Interstate 90 East - Billings (Photo taken 5/25/16).

View on Interstate 15 South as it prepares to merge into Interstate 90 West. I-15 and I-90 will run concurrently through Butte for roughly 8 miles. (Photo taken 5/25/16).

Take Exit 127 to the State Korean Vets Memorial and Civic Center. (Photo taken 5/25/16).

Also take Exit 127 to Highlands College. During this Interstate 15 / Interstate 90 concurrency, the mileage and exit numbers are based off the mileage of Interstate 15. (Photo taken 5/25/16).

Take Exit 126 to Butte Historic District and the Visitor Information and Transportation Center. (Photo taken 5/25/16).

Interstate 15 South / Interstate 90 West at Exit 127: Interstate 15 Business Loop / Interstate 90 Business Loop - Harrison Ave (Photo taken 5/25/16).

Section 4: Butte (Exit 127) to Dillon (Exit 63)

   

Interstate 15 South / Interstate 90 West reassurance shields. (Photo taken 5/25/16).

The speed limit remains 65 mph for all traffic as you pass through the Butte area. (Photo taken 5/25/16).

Again, take Exit 126 to Butte Historic District and for Visitor Information and the Transportation Center. (Photo taken 5/25/16).

Also take Exit 126 to Montana Tech of the University of Montana. (Photo taken 5/25/16).

Interstate 15 South / Interstate 90 West at Exit 126: Montana St (Photo taken 5/25/16).

Another set of Interstate 15 South / Interstate 90 West reassurance shields. (Photo taken 5/25/16).

Interstate 15 South / Interstate 90 West at mile marker 125. (Photo taken 5/25/16).

Interstate 15 South / Interstate 90 West at the Weigh Station in Silver Bow County. (Photo taken 5/25/16).

View of the ramp to the Weigh Station. (Photo taken 5/25/16).

Take Exit 121 to Port of Montana Transportation Hub. (Photo taken 5/25/16).

Interstate 15 South / Interstate 90 West at Exit 122: Rocker (Photo taken 5/25/16).

Approaching Exit 121, the standard rural speed limit of 80 mph for cars resumes as Interstate 15 South / Interstate 90 West leave the Butte area. (Photo taken 5/26/16).

Take Exit 121 to Port of Montana Transportation Hub and Dillon. (Photo taken 5/26/16).

Interstate 15 South / Interstate 90 West at Exit 121: Interstate 15 South - Dillon / Idaho Falls (Photo taken 5/26/16).

View of the ramp for Exit 121 to remain on Interstate 15 South. (Photo taken 5/26/16).

View on Interstate 15 South as it departs from Interstate 90 West and curves to the south ahead once again. (Photo taken 5/26/16).

Interstate 15 South as it curves to the south to the west of the Butte area. (Photo taken 5/26/16).

Interstate 15 South at mile marker 121. (Photo taken 5/26/16).

Interstate 15 South reassurance shield. (Photo taken 5/26/16).

Interstate 15 South at Exit 119: Hub Access / Silver Bow (Photo taken 5/26/16).

The speed limits remain 80 mph for cars and 65 mph for trucks. (Photo taken 5/26/16).

Mileage sign on Interstate 15 South. It's 17 miles to Divide, 56 miles to Dillon, and 203 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at mile marker 119. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 116 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 116: Buxton (Photo taken 5/26/16).

Interstate 15 South at mile marker 113. (Photo taken 5/26/16).

Interstate 15 South as it crosses the Continental Divide for a second time. This time the elevation is 5,879 feet. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 111 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 111: Feely (Photo taken 5/26/16).

Interstate 15 South reassurance shield. (Photo taken 5/26/16).

Another mileage sign on Interstate 15 South. It's 8 miles to Divide, 47 miles to Dillon, and 194 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at a Rest Area in southern Silver Bow County. (Photo taken 5/26/16).

Interstate 15 South at mile marker 108. (Photo taken 5/26/16).

Interstate 15 South at mile marker 105. (Photo taken 5/26/16).

Take Exit 102 to Big Hole Battlefield National Monument. (Photo taken 5/26/16).

Interstate 15 South at Exit 102: MT 43 - Divide / Wisdom (Photo taken 5/26/16).

Interstate 15 South will traverse a steep 6% downgrade ahead. (Photo taken 5/26/16).

Interstate 15 South at mile marker 100, heading down the grade. (Photo taken 5/26/16).

Interstate 15 South at Exit 99: Moose Creek Road (Photo taken 5/26/16).

After the 6% downgrade, another one exists ahead. This one is slightly milder at 5%. (Photo taken 5/26/16).

Watch for deer crossing the roadway. (Photo taken 5/26/16).

View on Interstate 15 South. (Photo taken 5/26/16).

Interstate 15 South at mile marker 95. (Photo taken 5/26/16).

Interstate 15 South at Exit 93: Melrose (Photo taken 5/26/16).

Interstate 15 South entering Madison County. (Photo taken 5/26/16).

Interstate 15 South reassurance shield. (Photo taken 5/26/16).

Mileage sign on Interstate 15 South. It's 7 miles to Glen, 29 miles to Dillon, and 176 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at mile marker 92. (Photo taken 5/26/16).

Interstate 15 South at mile marker 90. (Photo taken 5/26/16).

Interstate 15 South at mile marker 87. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 85 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South entering Beaverhead County. (Photo taken 5/26/16).

Interstate 15 South at Exit 85: Glen (Photo taken 5/26/16).

Another Interstate 15 South reassurance shield. (Photo taken 5/26/16).

Interstate 15 South at mile marker 84. (Photo taken 5/26/16).

Interstate 15 South at mile marker 80. (Photo taken 5/26/16).

Interstate 15 South as it enters the Pioneer Mountains. (Photo taken 5/26/16).

Interstate 15 South at mile marker 76. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 74 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 74: Apex / Birch Creek (Photo taken 5/26/16).

Mileage sign on Interstate 15 South. It's 10 miles to Dillon, 14 miles to the junction of MT 278, and 157 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at mile marker 68. (Photo taken 5/26/16).

Take either of the next 2 exits to Dillon. (Photo taken 5/26/16).

Take Exit 63 to the Beaverhead County Museum. (Photo taken 5/26/16).

Also take Exit 63 to University of Montana Western. (Photo taken 5/26/16).

Interstate 15 South at Exit 63: Interstate 15 Business Loop / MT 41 - Dillon / Twin Bridges (Photo taken 5/26/16).

Section 5: Dillon (Exit 63) to Idaho Border

   

Interstate 15 South at Exit 62: Dillon (Photo taken 5/26/16).

Take Exit 59 to Bannack State Park. (Photo taken 5/26/16).

Interstate 15 South at Exit 59: S-278 - Jackson / Wisdom (Photo taken 5/26/16).

Mileage sign on Interstate 15 South. It's 2 miles to Barretts, 34 miles to Dell, and 141 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at mile marker 58. (Photo taken 5/26/16).

Interstate 15 South at Exit 56: Barretts (Photo taken 5/26/16).

Parking Area on Interstate 15 South in Beaverhead County. (Photo taken 5/26/16).

Interstate 15 South at mile marker 54. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 52 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 52: Grasshopper Creek (Photo taken 5/26/16).

View on Interstate 15 South. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 51 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 51: Dalys (Photo taken 5/26/16).

Interstate 15 South crossing the Beaverhead River. (Photo taken 5/26/16).

Interstate 15 South at mile marker 47. (Photo taken 5/26/16).

Interstate 15 South at mile marker 46, crossing the Beaverhead River yet again. (Photo taken 5/26/16).

Take Exit 44 to a Recreation Area. (Photo taken 5/26/16).

Take Exit 44 to Grant as well. (Photo taken 5/26/16).

Interstate 15 South at Exit 44: S-324 - Clark Canyon Reservoir (Photo taken 5/26/16).

Interstate 15 South at mile marker 41. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 37 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 37: Red Rock (Photo taken 5/26/16).

Another Parking Area in Beaverhead County on Interstate 15 South. (Photo taken 5/26/16).

Interstate 15 South at mile marker 33. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 29 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 29: Kidd (Photo taken 5/26/16).

Mileage sign on Interstate 15 South. It's 5 miles to Dell, 15 miles to Lima, and 112 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at mile marker 28. (Photo taken 5/26/16).

Interstate 15 South at Exit 23: Dell (Photo taken 5/26/16).

Interstate 15 South at mile marker 17. (Photo taken 5/26/16).

Interstate 15 South at the Weigh Station in southern Beaverhead County. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 15 - 3/4 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 15: Lima (Photo taken 5/26/16).

Interstate 15 South reassurance shield. (Photo taken 5/26/16).

Interstate 15 South approaching Exit 9 - 1/2 mile. (Photo taken 5/26/16).

Interstate 15 South at Exit 9: Snowline (Photo taken 5/26/16).

Mileage sign on Interstate 15 South. It's 8 miles to Monida and 90 miles to Idaho Falls. (Photo taken 5/26/16).

Interstate 15 South at mile marker 6. (Photo taken 5/26/16).

Interstate 15 South at mile marker 4. (Photo taken 5/26/16).

Interstate 15 South at mile marker 2. (Photo taken 5/26/16).

Interstate 15 South at Exit 0: Monida. Ahead, Interstate 15 enters Idaho after a long 397-mile journey through the beauty of Montana. (Photo taken 5/26/16).