There are four small museums in the Citadel run by Heritage Malta. Entry to all four is covered by a joint ticket. Alternatively if you are planning to visit Ggantija Temple, Ta’Kola windmill and sites on Malta, a 30 day pass may be better value. This gives free entry to all Heritage Malta site (except the Hypogeum) for €30 or €22 for senior citizens. We didn’t visit the Natural History Museum. I have written separate reviews for each of the museums.
The Old Prison Museum overlooks Cathedral Square and is next to the Law Courts. It was built in 1548 to hold errant knights (usually for duelling) and locals. They could be held from a few months to ten years. Incarceration was coupled with hard labour. The daily food allowance was bread, pasta, some cheese or salted fish and, occasionally, some olives. There was a cistern in the corridor supplying water.
The entrance hall functioned as a common cell in 19thC and was used into 20thC. It has a small exhibition about the fortifications of Gozo. In the corridor there are information boards about life in the prison. There is a free standing block of 6 cells next to the central corridor which still have the original heavy wooden doors with massive iron locks. Inside is a wooden sleeping bench and a tiny window above the door for light.
Most impressive feature was the carved graffiti on the walls. We could see hand prints, complete with finger nails, Maltese cross, floral patterns, boats, some with oars and some with holes for cannons. There were tally lines used to count how long a prisoner had been incarcerated. In other places names and numbers had been carved. This was a well worthwhile visit.