The Old Jail Museum contains about 72 rooms, 27 cells, and basement dungeon cells that were used as solitary confinement until 1980. The 2nd floor also houses cells for women as well as a sitting room.

The Museum is more popular for being the site of the hanging of 7 Irish coal miners, known as Molly Maguires. It is also known as the site where Alexander Campbell, Edward Kelly, John Donohue, and Michael Doyle were hanged at the same time on gallows that were erected inside the cell block. That day was known as the Day of the Rope.

As the hanged men proclaimed their innocence before their deaths, many historians believe that some of them are, indeed, innocent. Up to this day, visitors can still see Alexander?s handprint, which he said will remain to prove his innocence.