Lemhi Pass

Lemhi Pass
View from Lemhi Pass
Elevation	7,373 ft (2,247 m)
Traversed by	Unpaved road
Location
Location	Lemhi County, Idaho / Beaverhead County, Montana, United States
Range	Rocky Mountains
Coordinates	44°58′27″N 113°26′42″W

Lemhi Pass is a high mountain pass in the Beaverhead Mountains, part of the Bitterroot Range in the Rocky Mountains The pass lies on the Montana-Idaho border on the continental divide, at an elevation of 7373 feet (2247 m) above sea level.

History

The pass gained importance in the 18th century, when the Lemhi Shoshone acquired horses and used the route to travel between the two main parts of their homeland. From the time of the Louisiana Purchase in 1803 until the Oregon Treaty in 1846 the pass marked the western border of the United States. On August 12, 1805 Meriwether Lewis and three other members of the Lewis and Clark Expedition crossed the Continental Divide at Lemhi Pass. Lewis found a "large and plain Indian road" over the pass. This was the first time that white men had seen present-day Idaho:

We proceeded to the top of the dividing ridge from which I discovered immense ranges of high mountains still to the West of us wth their tops partially covered in snow

The next day Lewis met Cameahwait and his band of Shoshone, and returned with them across the pass to meet Clark. On August 26, 1805 the entire expedition crossed the pass.

In the early 19th century the pass was regularly used by the Blackfoot people, so that in 1824 Alexander Ross referred to the route as the Blackfoot route. At that time the pass itself was known as North Pass, to distinguish from South Pass. The pass derives its present name from Fort Lemhi, founded in 1855 by Mormon missionaries who were the first non-Indians to establish a sustained relationship with the Salmon River Indian people.

During the mining era the pass was used by stagecoaches, but the route fell into disuse after 1910, when the Gilmore and Pittsburgh Railroad was built through the nearby Bannock Pass. Only a single track dirt road now crosses the pass.

The pass was designated a National Historic Landmark in 1960.

Mineral resources

The Lemhi Pass area contains the richest deposits of thorium discovered in the United States. Rare earth elements have also been discovered in Lemhi Pass. Thorium is used for manufacturing high tech products such as cellphones, electric cars etc.

Lemhi Pass
U.S. National Register of Historic Places
U.S. National Historic Landmark
Lemhi Pass
Nearest city:	Tendoy, Idaho
Coordinates:	44°58′27″N 113°26′42″W
Built:	1805
Governing body:	USFS
NRHP Reference#:	66000313
Significant dates
Added to NRHP:	October 15, 1966
Designated NHL:	October 9, 1960

See also

• Mountain passes in Montana

External links

• National Park Service - Lemhi Pass
• Reading 2: Lemhi Pass and Lolo Trail from The Lewis & Clark Expedition: Documenting the Uncharted Northwest Name, a National Park Service Teaching with Historic Places (TwHP) lesson plan.
• National Register of Historic Places Registration: Lemhi Pass
• Accompanying 10 photos, from 1958 and 1962