The Old Idaho State Penitentiary

The Old Idaho Penitentiary operated for over 100 years as the first prison in Boise, Idaho. Over the years it has housed over 13,000 inmates, hosted 36 wardens, and was the site of numerous escapes, riots, and executions. Today, it stands as one of only four territorial prisons open to the public and has been converted to a museum detailing the prison’s history.

Located between the heart of downtown Boise and the Boise Foothills, the Old Idaho Penitentiary serves as a reminder of Idaho’s territorial past. Inmates quarried the distinctive sandstone that makes up the prison’s buildings and walls from the nearby Table Rock area, a well-known Boise landmark. The penitentiary first opened in 1872 and was originally known as the Territorial Prison. It was later renamed the Idaho State Penitentiary when Idaho achieved statehood in 1890.

The prison was constructed in the Second Empire architectural style with guard turrets and thick walls reminiscent of a castle or fortress. Architects intended the construction to evoke a “somber, dark environment deemed appropriate for prisoners.” Wardens and guards encouraged inmates to work to reduce idleness and the penitentiary became almost entirely self-sufficient. Inmate labor carried the added benefit of reducing construction fees, costs, and wages significantly, saving the state hundreds of thousands of dollars. However, the prison lacked modern amenities, a problem that would cause discontent and riots in later years.

As the number of inmates increased, the compound expanded significantly. The inmates quarried sandstone and constructed most of the buildings themselves. By 1973, the penitentiary’s walls had housed multiple cell blocks, several administrative buildings, the warden’s house, a dining hall, library, commissary, blacksmith and carpenter shop, shirt and license plate factory, women’s ward, an apiary, a garden, and a steam plant. The prison also contained several isolation and punishment cells, known as the “Dungeon,” “Cooler,” and “Siberia,” as well as a gallows that was used to execute ten prisoners. Additionally, the penitentiary owned several ranches and farms that utilized inmate labor to produce the prison’s food.

Harry Orchard was the penitentiary’s most infamous prisoner. He had assassinated Frank Steunenberg, the former governor of Idaho, with a bomb as revenge for the government’s role in the 1890 mining conflicts in Coeur d'Alene. Although he confessed to killing at least 17 men, Orchard remained a model prisoner. Other prisoners were not, and the penitentiary experienced over 500 escape attempts. Prisoners escaped by running away from work assignments, digging tunnels, climbing walls, or lowering themselves down makeshift ropes. Some succeeded, but the majority were caught soon after their escape. 

There were also several riots in the later years of the penitentiary's history, reflecting inmate discontent with outdated prison conditions. One of the most notable riots occurred in 1952, when nearly 250 inmates seized the Multipurpose Building and severely damaged it. In 1971, two prisoners were stabbed, inmates set fire to several buildings, and others raided the commissary and hospital. A similar riot occurred in 1973 and caused significant fire damage. The riots were all put down, some using tear gas, but the increasing frequency worried prison officials. 

The riots, outdated facilities, and lack of space for expansion led to the construction of a new correctional facility in 1972. This facility was built near Kuna, Idaho, and officials gradually transferred inmates there. By 1974, the recently renamed Old Idaho Penitentiary earned a spot in the National Register of Historic Places. Today, it has been converted into a museum run by the Idaho State Historical Society. Boise residents refer to it as the “Old Pen,” and local legend claims it is haunted by the ghosts of former guards and executed inmates.


Women's Ward
Women's Ward Aerial View of the Women’s Ward, with the main prison in the background. Source: Tamanoeconomico. Old Idaho State Penitentiary. March 9, 2019. Via Wikimedia Commons.
South Wing Cell Block
South Wing Cell Block Source: Paramedic1952. 3 House (South Wing) Interior. May 20, 2011. Via Wikimedia Commons.
The Administrative Building
The Administrative Building Backside of the1950s Administrative Building. Source: Paramedic1952. Admin Building Back. August 31, 2006. Via Wikimedia Commons.
Southwester Turret and Penitentiary Wall
Southwester Turret and Penitentiary Wall Source: Madison Sommer, Southwestern Turret and Penitentiary Wall, 2022, Private Collection, Boise.
The Northwestern Turret
The Northwestern Turret Source: Madison Sommer, The Northwestern Turret, 2022, Private Collection, Boise.
The Administrative Building
The Administrative Building Note the Second Empire architectural style. Source: Madison Sommer, The Administrative Building, 2022, Private Collection, Boise.



Madison Sommer, Brigham Young University, “The Old Idaho State Penitentiary,” Intermountain Histories, accessed April 16, 2024,