Boise is a city located in the Northwestern United States in the state of Idaho. Boise is the capital and most populous city of the U.S. state of Idaho as well as the county seat of Ada County. Boise serves as the principal city of the Boise City-Nampa metropolitan area and is the largest city between Salt Lake City, Utah and Portland, Oregon, and thus serves as the primary government, economic, cultural, and transportation center for the area.
As of the 2007 Census Bureau estimates, Boise's population was 202,832 with a metropolitan area estimated to have 587,689 inhabitants, making it the most populous metropolitan area in Idaho and the fourth largest in the Pacific Northwest.
Boise is located at 43° 36' 49"N 116° 14' 16"W / 43.613739, -116.237651) in southwestern Idaho, approximately 41 miles east of the Oregon border, and 110 miles north of the Nevada border. The downtown core sits at an elevation of 2,704 feet (824 m) above sea level.
It is commonly accepted that the area was referred to as Boise long before the establishment of Fort Boise. However, the exact details of how the name came to be applied to the area differ in the available accounts.
Some credit a story told of Captain B.L.E. Bonneville of the U.S. Army as the source of the name. After trekking for weeks through dry and rough terrain, his exploration party reached an overlook with a view of the Boise River Valley. The place where they stood is called Bonneville Point, and is located on the Oregon Trail east of the city. According to the story, a French-speaking guide, overwhelmed by the sight of the verdant river, yelled "Les bois! Les bois!" giving the area the name.
But the name "Boise" may actually derive from earlier mountain man usage, which contributed their naming of the river that flows through it. In the 1820s, French Canadian fur trappers set trap lines in the vicinity where Boise now lies. In a high desert area, the tree-lined valley of the Boise River became a prominent landmark. They called this "La rivière boisée", which means "the wooded river."
The original Fort Boise was 40 miles west, down the Boise River, near the confluence with the Snake River at the Oregon border. This fort was erected by the Hudson's Bay Company in the 1830s. It was abandoned in the 1850s, but massacres along the Oregon Trail prompted the U.S. Army to re-establish a fort in the area in 1863, during the U.S. Civil War. The new location was selected because it was near the intersection of the Oregon Trail and a major road connecting the Boise Basin (Idaho City) and the Owyhee mining areas. Both areas were booming at the time. Idaho City was the largest city in the area, and as a staging area to Idaho City, Fort Boise grew rapidly. Boise was incorporated as a city in 1864. The first capital of the Idaho Territory was Lewiston, but Boise replaced it in 1865.
The U.S. Assay Office at 210 Main Street was built in 1871 and is a National Historic Landmark.