Boise County is named for the Boise River, which was named by French Canadian explorers and trappers for the great variety of trees along its bank and “boise” is the French word for “wooded”.
Surrounding County Courthouses:
N – Valley County
E – Custer County and Blaine County
S – Elmore County
W – Ada County and Gem County
Created: February 4, 1864 
County Seat:
Idaho City 1864 – present
County Courthouse – Idaho City
Location: 419 Main Street / Wall Street
Built: 1871
Style: Federal
Architect: C S Kingsley and E A Kingsley
Contractor: C S Kingsley and E A Kingsley
Description: The building faces east and is a one story red colored brick and wood structure. The building was constructed as a general store and was bought by the County in 1909. A porch extends around three sides and is supported by thin posts. The slanted roof is colored blue.
See: The 4th Judicial District includes Ada County, Elmore County and Valley County.
Note: The courthouse is the oldest courthouse in Idaho still used as a courthouse.
County Courthouse – Idaho City
Photos taken 2009