Galicia's most spectacularly sited prehistoric settlement is poised majestically on a wind-blasted headland overlooking the Atlantic waves, 4km southwest of Porto do Son. Park near Cafe-Bar Castro and take the rocky 600m path down to the ruins. Clearly the exposed location was chosen for its defensive qualities: a moat and two stone walls protect its access across a small isthmus. Inside are the excavated bases of about 20 round stone buildings. The settlement was abandoned in the 1st century AD. Stretching south from the castro, Praia Area Longa is a nudist beach and also the first of a string of surfing beaches down this side of the ría.