The City of Mdina has a long history built on the site occupied by many civilizations. The site probably originated as a Bronze Age hilltop settlement, but it was under the Phoenicians that the site was given the first resemblance of a town. Records dating back to 350 BC indicate that the city was already fortified. The city fell under Roman influence after it was conquered by the Romans at the end of the second Punic War in 218 BC. Later civilizations continued fortifying and strengthening the city until it has become the Mdina we know today. These layers of more than 2000 years of civilisation can be seen at the Mdina Cathedral. Built deep own and sewn in the limestone beneath Mdina Cathedral crypt, one can find a large basement complex dating as far back as the Roman period and possibly before.
Beneath the cathedral church are two massive Roman walls with a junction. These are clear traces of a fortified city. There is also a Roman rock-cut water tank with an arched entrance. One can also find remains of some ornate Timber beams. One of these beams had been taken for conservation in the Cathedral Museum.
In 1996 the Central Bank of Malta published a book in two volumes written by Prof. Mario Buhagiar and Prof. Stanley Fiorini in which one could find plans and photos of these underground cellars (some of which are being reproduced below). In recent years the basement has been left empty and not used for any specific purpose.