An extraordinary system of cultural and historical resources.

Old Idaho Penitentiary History

Come and Explore Over a Century of Prison History!

historic photo of cellhouse interiorThe Old Idaho Penitentiary was a functioning prison for 101 years.  It was built in 1870, and the first prisoners arrived in 1872.  The four and a half-acre site was selected because of its proximity to the growing agricultural center in Boise and to sandstone, the material used in the construction of the penitentiary’s walls, Administration Building, and cell houses.  The buildings on the site were built by inmate laborers. 

In 1872, the Idaho Territorial Penitentiary officially opened.  The Old Idaho Penitentiary grew from a single cell house into a complex of several buildings holding Idaho's most notorious criminals. The "Old Pen" received over 13,000 inmates with a maximum population of overcurrent photo of cellhouse interior 600 inmates. There were 222 female inmates, including repeat offenders.

The federal government operated the site until statehood in 1890. The “Old Pen”, as it is affectionately referred to by locals, officially closed in December 1973.

  • Do you want to volunteer for our Halloween event? Click here for the Volunteer Form and e-mail your completed form. Please complete all the fields on the form.