The Castello della Colombaia occupies a small islet at the entrance to Trapani harbour, connected to the mainland by a causeway. The fortification dates in its current form to the 15th century, built on foundations that go back to Roman or earlier times. Its cylindrical tower dominates the harbour entrance and appears in most photographs of Trapani taken from the sea.
The castle is undergoing restoration and access has been limited in recent years; check locally for current opening status. The exterior view from the harbour walls or from the bridge connecting the old town to the port is excellent. The castle on its islet with the salt pans and Monte Erice visible in the background is one of the standard images of Trapani.