The Castello – or more precisely Castellammare – had ancient origins. Its original nucleus was built by the Arabs at the mouth of the Cala. Over the centuries it was repeatedly enlarged and strengthened. In addition to external defense, it also served to curb Palermo’s restless and turbulent population. From fifteenth century it was first, the seat of the viceroy, then a prison for the noble class and for offenders of the State. After the revolution of 1860 it was partially dismantled by the insurgent people and in 1922 was largely demolished to make room for the creation of the pier. Only the remains of the Arab keep and the Arogonese entrance remain. RLD, 385, AC, 119.