Old Idaho Penitentiary

The Old Idaho Penitentiary State Historic Site was a functional prison from 1872 to 1973 in the western United States, east of Boise, Idaho. The first building, also known as the Territorial Prison, was constructed in the Territory of Idaho in 1870; the territory was seven years old when the prison was built, a full two decades before statehood.

From its beginnings as a single cell house, the penitentiary grew to a complex of several distinctive buildings surrounded by a 17-foot-high sandstone wall. The stone was quarried from the nearby ridges by the resident convicts, who also assisted in later constructions.