An infamous prison even before the Resource Wars kicked jingoism across the United States into high gear, the ERP housed criminals from all over Appalachia. Budget and staff cuts prevented substantial renovations to the buildings, with some corrections officers raising the possibility of the prisoners one day simply pulling the bars off from the walls. The solution to the problem was to eliminate the need for walls at all: All prisoners were fitted with explosive collars no matter the severity of their crime, from unpaid parking tickets to the most hardened, serial criminals permanently sealed in solitary confinement, like Mad Dog Malone. Warden Brennan was an enthusiastic advocate of these new measures and pushed for a full automation of the prison under the new Appalachian zeitgeist. He was successful, and for his loyal service, he was designated the sole human overseer of the facility until his retirement and benefits. Everyone else on the staff was discharged, leaving the inmates in the hands of uncaring robots and a perfectly logical mainframe that knew not nuance.
In the end, the ERP became little more than an automated concentration camp. Cell Block D was used nominally for organized crime, but its inmates counted union organizers and Communists, with block C used for solitary confinement. Only blocks A and B had a degree of livability, meant as Minimum Security and General Population blocks, respectively. The Great War saw fit to wipe society and the forgotten inmates were reduced to feral ghouls by the passage of time and radiation. By 2102, the prison is shared between super mutants on the outside and ghouls on the inside, together with plenty of traps.
The prison is located on the edge of the Toxic Valley and is clearly identifiable due to its tall sandstone walls and towers ringing the perimeter. Super mutants are plentiful, primarily inside the prison yard.
The yard contains storage sheds in the northeastern part, which contain several workstations for power armor, weapons, armor, and tinkering. Just next to them is the exercise yard, with a church and office pods on the opposite, western side of the yard.
The interior of the penitentiary wraps around the southern edge of the penitentiary and contains four cell blocks spanning two floors each, with two per wing. They are joined together by the prison administration building in the center, which contains the entrance, visiting, intake and processing room with automated barber chairs, with the warden mainframe and derelict robot storage on the upper floor.
- Thomas Brennan's announcement - Holotape, located on the coffee table in the warden's office.
- Penitentiary key - Seven keys throughout the facility, used to open jail doors and security gates.
- Penitentiary security password - Given by the Warden during Falsely Accused. Gives access to security terminals.
- Four potential Vault-Tec bobbleheads:
- One is located in the south guard tower.
- One is located on the bump out of the perimeter wall under the north tower.
- One is located in a cell on the second floor in cell block B; it can only be accessed if the player character jumps to it, and it is on top of a safe within the cell.
- One is located on the southeast corner of the prison roof behind two vents, next to a cap stash.
- Two potential magazines:
- Inside the intake room near cell block D, on a corner table on the right.
- On a shelf in one of the trailers in the yard (above a chem box).
- Power armor chassis - Occasionally spawns in the Penitentiary courtyard within a shack with three power armor stations.
- Civil Unrest - Given as a reward for completing Falsely Accused.
- Plan: Water filter - Inside the intake room near cell block D, on a corner table on the right.
- Random weapon mod - Inside the courtyard, on a metal shelf to the left of two armor workbenches.
- Two Addictol - Respawning, behind a door opened with a zero skill computer terminal.
The Eastern Regional Penitentiary appears only in Fallout 76.