Praia do Ouro — "Gold Beach" — is the long sweep of sand that runs the length of Sesimbra's waterfront, from the Fortress of Saint James at the eastern end to the fishing harbour in the west. It is south-facing, sheltered by the cliffs of the Arrábida from the prevailing northerly wind, and the warmest swimming on the Lisbon coast — the water is typically two or three degrees warmer than at Cascais or Estoril.
The sand is fine and pale, the bottom shallow and gentle, and the beach is fully serviced — lifeguards in season, sun-lounger rental, a string of restaurants and bars along the promenade behind it. In July and August it is busy with day-trippers from Lisbon; outside July and August it is wonderful. The eastern end, nearer the fortress, is quieter; the western end has the better cafés.