While most Gothic Revival buildings attempt to recall the graceful, spiritually uplifting forms of a medieval cathedral, this jail is modeled on a castle. The heavily crenellated building of Clarion County golden sandstone has two projecting towers on the facade and a high watchtower in the center. The main entrance is recessed between the two towers. Special features are incorporated into the design to prevent prisoners from escaping. Between a convict and freedom are two-and-one-half feet of brick threaded with steel bands to prevent tunneling, and a series of iron plates in the floor to prevent digging. The roof has been reinforced since its original construction. A brick version (1873–1874) of this building, also designed by James McCullough, stands in Clarion (
CL2), and the 1868–1869 prison in Hollidaysburg, Blair County, designed by Edward Haviland, may have been the model (
BL3). In 1981, L. Robert Kimball redesigned the cell blocks, guardrooms, control center, and visiting area, turning what was originally the warden's apartment into offices and installing modern security devices.