The roots of corrections are in Idaho City and Lewiston. The territorial legislature designated the two cities jails as territorial prisons in 1864. During the eight years the jails served the territory, they housed approximately 100 inmates. The majority of inmates were in Idaho City. Much of the original Idaho City territorial prison fell into Elk Creek when gold diggers undermined the area in the early 1900s. The remaining buildings were moved into Idaho City where they remain today.

An Idaho Historical Society document from 1964 provides a glimpse into make-shift prisons that served the territory. Another treasure trove of information is a recently developed catalogue of Idaho Inmates .

The federal government began work on a more permanent structure in 1870 using inmate labor to help build a sandstone prison. The territorial prison opened in 1872. When Idaho became a state in 1890, the state took over and renamed the facility the Idaho State Penitentiary. The prison housed inmates for 101 years before it was closed in December 1973 after inmates rioted over living conditions. The sandstone structure is now a museum.

The oldest prison still in service is the Idaho State Correctional Institution. It opened in 1972 and replaced the territorial prison. ISCI still houses medium custody male inmates. A radar station and mental health hospital were converted to house inmates in the 70s and 80s. Additional facilities were added over the years.

In addition to prisons, the department supervises offenders living in Idaho communities and provides education, treatment and reentry services to help reduce recidivism.

The Old Pen

Much of IDOC's history is on display at the Old Idaho State Penitentiary off of Warm Springs Avenue east of Boise. The site is now maintained by the Idaho Historical Society. Visitors can tour the old cell blocks, view photographs of the facility when it was in operation and learn about some of the notable inmates who were incarcerated there. They include Harry Orchard, who assassinated Idaho Governor Frank Steunenberg in 1905, and Lyda Southard, who was known as Idaho's Lady Bluebeard. She was convicted of killing several of her husbands to collect their life insurance.

The Old Pen is open seven days a week except for state holidays. To learn more, visit the Idaho Historical Society’s website.