Bonneville County is named for Benjamin L E Bonneville, who was a French born explorer and who lived from 1796 to 1878.
Surrounding County Courthouses:
N – Jefferson County, Madison County and Teton County
E – Teton County, Wyoming and Lincoln County, Wyoming
S – Caribou County and Bingham County
W – Bingham County
Created: February 7, 1911 
County Seat:
Idaho Falls 1911 – present
County Courthouse – Idaho Falls
Location: 605 North Capital Avenue / C Street
Built: 1920 – 1921
Style: Neo-Classical
Architect: Charles Aitken and Lionel E Fisher
Contractor: W H Holden and E M Holden
Description: The building faces east and is a two story brick, stucco, sandstone and concrete structure. The building is located on landscaped grounds in the center of Idaho Falls. The east front has a projecting center section with recessed entrance. The roof line is flat. The interior has marble stairs which lead up to a wide hallway which opens up into the central foyer. All floors in these public spaces are of white colored vitreous mosaic tile and an Alaska marble wainscot graces the walls. The woodwork and beamed and paneled ceiling also remain in their original form. The central foyer has a balustraded square opening which looks down to the ground floor. The stained glass skylight with the Bonneville county crest is above this opening. The courtroom is located on the second story. The building houses the County District Court and County Magistrate Court of the 7th Judicial District. On the south side is a modern addition which is attached to the main building.
Note: Other contractors were North Pacific Construction Company, S K and George Mittry to complete the building, and to Tarbet Heating and Plumbing to install the plumbing and heating works. There was no money left to pay the remainder of the amount incurred by the Mittry brothers of $18,880 and the company went out of business.
See: National Register of Historic Places – Bonneville County Courthouse
See: The 7th Judicial District includes Bingham County, Butte County, Clark County, Custer County, Fremont County, Jefferson County, Lemhi County, Madison County and Teton County.
History: The county was created in 1911 and Idaho Falls was designated as the county seat. The county used rented premises. The first and present courthouse was constructed in 1921 to 1922 at a cost of $250,000.
County Courthouse – Idaho Falls
County Courthouse Addition – Idaho Falls
Photos take 2011