The Portara, the great marble gate that stands high on the islet of Palatia, now united with Naxos town, is what remains of the Temple of Apollo, which to be built around the 6th-7th century BC but was never completed.
The gate is around 6 m high and 3.5 m wide built with four separate columns. Each column weighs about 20 tons. During the Middle Ages, a church was built behind the Portara. Later under Venetian rule, it was dismantled so that the marble could be used to build the Kastro, which is a fortress built during the time of the Venetians and other monuments and buildings.