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Interstate 15 –
|Interstate 86, Pocatello
count in 2005
|8.858, Malad traffic
2,678, Spencer traffic recorder
Interstate 15 journey
known as Route 3, Interstate 15 begins at the Utah State Line north of Logan,
Utah, continues north through Pocatello and Idaho Falls to the Idaho/Montana
On a regional
scale, this stretch of 196 miles later became Interstate 15.
I-15 is the fourth longest north-south transcontinental highway, traveling through
Montana, Idaho, Utah, Arizona, Nevada and California. The highway is a non-stop
link between San Diego and the shipping ports there through the western slope
of the northern Rockies.
highway begins in Idaho's southeastern highlands, on the northern tip of Utah’s
Wasatch Front. It shoots like an arrow directly north, with the first major
Idaho stop in Malad (pronounced mah-LAD), just before Malad Summit. The highway
continues north through the Caribou National Forest, splitting islands of timber
stands interspersed with high wheat fields and bitter brush ranges.
summit, the highway follows the Marsh Creek and then Portnuef (PORT-nuff) River
before taking a 90-degree jog west at Inkom. The interstate closely follows
the Portneuf River to Pocatello, where it veers north and east of the city,
joining with Interstate 86 at the suburb of Chubbuck.
continues north through the Fort Hall (Shoshone-Bannock) Indian Reservation,
which offers travelers numerous shopping and entertainment amenities, including
an Indian gambling casino, popular with eastern Idaho and Utah residents.
north, vacationers typically leave I-15 at Idaho Falls to join State Highway
20, which leads northeast to Yellowstone National Park. Meanwhile, the Interstate
rises gradually toward Montana as open fields give way to stands of lodge pole
an extended season in this region, with snow flurries sometimes beginning in
early September and snow remaining on the ground well into May at some higher