The remains of six Punic-Roman towers have been identified in Malta. They are believed to have been built while the island was part of the Punic or Roman Empires. Their architecture suggests a late Punic origin, and they remained in use throughout the Roman period, until at least the 3rd century AD. Evidence suggests that the towers were used to defend the island. The towers are clearly all built on high grounds, in specific locations, and could considerably communicate with signals from one to another. Similar towers are also found in nearby Tunisia with the same defensive system. In the context of time some locals still lived in caves with few others living in vernacular housing with similar characteristics to nearby Sicily.