Beaverhead County is named for Beaverhead Rock in the Jefferson River, which rock is shaped like a beaver’s head.
Surrounding County Courthouses:
N – Ravalli County, Granite County and Deer Lodge County
E – Silver Bow County, Madison County and Fremont County, Idaho
S – Clark County, Idaho and Lemhi County, Idaho
W – Idaho County, Idaho
Created: February 2, 1865 
County Seat:
Bannock 1865 – 1881
Dillon 1881 – present
County Courthouse – Dillon
Location: 2 South Pacific Street / East Bannock Street
Built: 1889 – 1890
Style: Classical Revival
Architect: Sidney Smith
Contractor: Wincote and Riley of Omaha, Nebraska
Description: The building faces northwest and is a two story buff colored brick and wood structure. The building is located on landscaped grounds in the center of Dillon. The northwest front has a wide arch at the central entrance. The center section rises into a large square tower with clock and cupola at the top. The second story windows are arched. The base of the building is course stone. The building houses the County District Court of the 5th Judicial District. An addition has been added on the southeast side. An addition was constructed on the east side in 1974 and 1975. The architect was Johnson-Graham Associates and the contractor was Robert A Taylor Construction.
Old County Courthouse – Bannack
Location: Main Street
Built: 1875
Style: Federal
Architect: Unknown
Contractor: Unknown
Description: The building faces south and is a two story red colored brick structure. The building is located on landscaped grounds in the center of Bannack. The south front has a porch with balcony on the second story. The roof is hipped. The building served as the courthouse until the county seat was moved to Dillon and then served as a hotel. The building is located in the Bannack State Park.
See: The 5th Judicial District includes Beaverhead County, Jefferson County and Madison County.
History: The county was created in 1865 and Bannock was selected as the county seat. The county offices were housed in two log cabins. The first courthouse was built in 1875 at a cost of $14,000. The county seat was moved to Dillon in 1881. The county used rented premises until the second and present courthouse was constructed in 1889 to 1890.
County Courthouse – Dillon
County Courthouse Addition – Dillon
Old County Courthouse – Bannack
Old County Jail – Bannack
Photos taken 2009 and 2011