The Sinis Peninsula west of Oristano has some of Sardinia's least-developed beaches. Is Arutas is the most famous, named for its quartz sand — tiny rounded white and pink pebbles rather than the usual golden grains, which gives the beach an extraordinary texture and colour. The water over the white pebble floor is vivid turquoise. Mari Ermi nearby is similar and usually quieter.
Further south, toward Tharros, the beaches become more rugged and windswept, with fewer facilities and fewer people. You'll need a car to reach most of them, and in July and August even Is Arutas gets busy — go early in the morning or come in June or September.