Saint Thomas Tower is a large bastioned watchtower in Marsaskala. It was built above the shore on the seaward face of the headland of il-Hamriga in Marsaskala. It is a substantial fortification intended to prevent the landing of troops in the sheltered anchorages of Marsaskala Creek and St Thomas Bay. Construction of the tower was approved in July 1614, weeks after the raid of Żejtun, in which an Ottoman fleet managed to land at St Thomas Bay. The tower was named after a chapel dedicated to St Thomas which stood close to where the tower now lies.
The tower has very thick walls and has four pentagonal bastioned turrets projecting outwards on each corner. The tower's entrance was through a vaulted doorway with a wooden drawbridge. The drawbridge is still partially intact and it is the only original one to have survived in Malta. The tower is surrounded by a rock-hewn ditch.
After the De Redin towers were built, St Thomas had Żonqor and Xrobb l-Għaġin Towers in its line of sight, but these are now either in ruins or completely demolished.
In 1715, St Thomas Tower was reinforced by the addition of a battery on the seaward face. During the French blockade of 1798–1800, the tower was stormed and captured by Maltese insurgents.
The tower remained in use by the British until the 19th century. At some point, the tower was also used as a prison.
References:The Basilica of Santa Maria in Trastevere is one of the oldest churches of Rome. The basic floor plan and wall structure of the church date back to the 340s, and much of the structure to 1140-43. The first sanctuary was built in 221 and 227 by Pope Callixtus I and later completed by Pope Julius I.
The inscription on the episcopal throne states that this is the first church in Rome dedicated to Mary, mother of Jesus, although some claim that privilege belongs to the Basilica di Santa Maria Maggiore. A Christian house-church was founded here about 220 by Pope Saint Callixtus I (217-222) on the site of the Taberna meritoria, a refuge for retired soldiers. The area was made available for Christian use by Emperor Alexander Severus when he settled a dispute between the Christians and tavern-keepers.
The church underwent two restorations in the fifth and eighth centuries and in 1140-43 it was re-erected on its old foundations under Pope Innocent II.