The Burlington County Prison Museum in Mount Holly, New Jersey is a stone jail built in 1811 that locked up prisoners for 154 straight years, making it the oldest continuously operating prison in the United States when it finally closed in 1965. Today you can walk the same cell blocks, stand in the execution yard, and hear the stories of the inmates — and the ghost — who never quite checked out.
You don’t expect a county jail to double as an architectural landmark, but this one does. It’s also, depending on who you ask at the gift shop counter, one of the most haunted buildings in the Garden State.
Who Built the Burlington County Prison, and Why Does It Matter?
The jail wasn’t designed by some anonymous county contractor. The Freeholders selected architect Robert Mills to design the Jail, and Mills, a Quaker, designed the Jail with the Quaker idea that inmates should be reformed through religious instruction, education and vocational training. Mills was in his twenties at the time, and this was one of his very first solo commissions. He went on to design some of the most recognizable buildings in America — the US Treasury Building, the US Patent Office, and the US Post Office, as well as the Washington Monument in Baltimore, and the National Monument in DC, which is a fancy way of saying the guy who designed the Washington Monument got his start building a county lockup in South Jersey.
Mills didn’t just design a holding pen. The Burlington County Prison was completed in 1811, and the interior vaulted ceilings of poured concrete and brick and stone construction made the building virtually fireproof. That construction quality is exactly why it lasted so long. It was so well constructed that it remained in constant use until 1965. Mills even picked the motto carved over the entrance himself: “Justice Which, While it Punishes, Would Endeavor to Reform the Offender.”
What Makes This the Oldest Prison in the Country?
It’s not a marketing exaggeration — it’s a documented fact. Operating from 1811 to 1965, it was the oldest operating prison in the nation at the time of its closure, designed with individual cells, good ventilation, and fireproof construction that reflected period thinking in progressive prison design. That streak of continuous use earned the building federal recognition: it’s now operated by a local nonprofit as a museum, and it was designated a National Historic Landmark in 1986, after being listed as a contributing property of the Mount Holly Historic District in 1973.
The jail wasn’t reserved for hardened criminals, either. Throughout its lifespan, the prison held inmates for crimes varying in severity from owing a debt and adultery to arson and murder. Flip through the old record books on display and you get a genuinely wild cross-section of 19th and 20th century small-town trouble — reading the old volumes of arrest records is entertaining, with a colorful lot of prisoners, crimes, and punishments to peruse. One notable alumnus passed through decades before becoming infamous elsewhere: among its “alumni” was a man named Albert DeSalvo, who was passing through Jersey and arrested on lewd and indecent exposure charges, and later “graduated” to notoriety as The Boston Strangler.
What Happened in the Exercise Yard?
This is where the museum stops being quaint. New Jersey law once required capital crimes to be punished in the county where they happened, and Burlington County’s gallows stood right in the prison yard. In the almost hundred years before New Jersey executions were moved to the state’s capital, Trenton, in 1905, seven people were hanged from the gallows in the Burlington County Prison yard, with two more people sentenced to death held in the prison but executed elsewhere. The last hanging on-site wasn’t ancient history by prison standards: the last hanging took place in 1906, on March 24, when convicted murderers George Smalls and Rufus Johnson were executed just two months after committing their crime.
You can still see where it happened. The gallows that now stands in the back prison yard is a replica, modeled after the one that stood in the same spot in 1890, with the drop floor boarded over for safety but still a macabre reminder of a time when tickets were given out and spectators entered the yard through a side door, eager to witness the latest execution. Executioners handed out tickets to a hanging. Let that sit with you for a second.
Is the Burlington County Prison Museum Haunted?
This is the question everyone actually wants answered, and the museum itself leans into it. The most-told ghost story centers on a condemned man named Joel Clough. Joel Clough had been arrested and convicted of the stabbing death of a woman in Bordentown — apparently she had jilted him — and though he managed to escape, the 29-year-old Clough was quickly recaptured and confined to the Death Cell on the upper floor of the prison. According to the museum’s own records, the first execution took place in 1718 and the last in 1922, with the first 32 carried out by hanging in or near Burlington City before the prison was built in 1811. Clough’s own date is on record: he was executed on July 26, 1833, for murder.
Supposedly, he never left. The first reports of spirits roaming the prison’s halls came in 1833, following the execution of Joel Clough, who was buried on the grounds — guards and prisoners heard moaning and rattling chains, and smelled cigarette smoke coming from the “dungeon.” That report was taken seriously enough that it prompted the Board of Freeholders to ask a paranormal team to investigate, and as a result the prison joined the ranks of the most haunted buildings in New Jersey. Television crews have since come looking for him too — the museum has been investigated by paranormal teams on camera over the years.
Staff don’t shy away from the reputation. One museum employee told a reporter he’s personally heard unexplained noises and seen shadowy figures throughout the prison. The museum’s president is refreshingly blunt about why people actually show up: “People come here for all sorts of reasons,” Janet Sozio, President of the Historic Burlington County Prison Museum Association, says, “but I must admit, most come because they want to find paranormal activity.”
What Can You See Inside?
Beyond the ghost lore, the building itself is the real draw for history buffs. The maximum-security “dungeon” cell where Clough spent his last night is preserved, complete with the iron floor ring once used to restrain condemned prisoners. Decades of inmate graffiti — poetry, calendars, religious messages — are still etched into the cell walls, offering a strangely intimate window into the people who did time there. If you want a lighter activity, the museum also runs a ticketed escape-room-style game where you play an inmate trying to break out, picking up clues floor by floor.
Visiting the Burlington County Prison Museum
The prison museum sits in the middle of historic downtown Mount Holly, within walking distance of other Revolutionary-era buildings. It’s located at 128 High Street in Mount Holly, open Thursday through Saturday with no reservations required, from 10 a.m. to 4 p.m. Admission won’t break the bank: adults pay $4, children, students, and seniors pay $2, and kids under 5 get in free.
If you want the spookier version of the visit, the county parks system rents out the building for after-hours paranormal investigations. Investigations run on Friday and Saturday evenings from 7 p.m. to midnight and are available year-round except in October, for a nominal fee. October itself is reserved for public programming instead, including free guided tours of the darker corners of the building’s past. Check the museum’s own site before you go, since hours and special events shift seasonally.
Whether you come for the architecture, the archives, or the chance that something in the dungeon might answer back, the Burlington County Prison Museum delivers a kind of history you can’t get from a plaque. You’re standing in rooms where real sentences were served, real escapes were attempted, and at least one execution left behind a story that’s still being told a century and a half later.
NOTE TO THE ADVENTURER: This guide is meant to spark curiosity for what lies beyond the horizon — not to serve as a guarantee. Roads fall into disrepair, buildings are torn down and rebuilt, and properties change hands; 'tis your responsibility to do your own research before setting out. Always heed local and regional law, and always respect ground that isn't your own. Take every entry here as a suggestion, not a decree. This guide's contents were gathered with the aid of artificial intelligence, and like any scout, it will from time to time lead you astray. You assume all risk in following its counsel, and neither this blog nor its author is liable for any loss, injury, or misfortune that results.
