The State Correctional Institution – Forest is one of two identical correctional facilities in Pennsylvania that were constructed in the beginning of the twenty-first century to hold maximum-security male inmates.

SCI Forest is located in the community of Marienville, in remote Forest County.

SCI - Forest and SCI-Fayette, which are identical in size and design, were constructed to accommodate overcrowding at SCI-Pittsburgh and SCI-Waynesburg, which were "mothballed"[1] after the opening of SCI Forest.

Construction of the correctional facility cost $126 million.