Day 4 · Monday
Mountains in the morning, the west coast in the afternoon. A blue spring at the foot of the Supramonte, two hours across the middle of the island, a rice-grain quartz beach, then a walk to the end of a cape to watch the sun set into the sea.
A big free car park at the gate. From here it’s a 5-minute walk, no cars.
Cost: Free
Navigate here ↗Pin40.28901, 9.49412
Sardinia’s largest karst spring: a deep blue-green crack at the foot of the Supramonte cliffs. Divers have gone down over 100 m and still not found the bottom. Walk about 300 m through the eucalyptus park, past the little church of Nostra Signora della Pietà, to the pool under the cliff. Toilets at the entrance.
Opening hours are listed as daily 09:00–20:00, but the date of that information is unknown. If the gate is shut, phone one of the numbers below.

No fixed speed cameras are mapped on this route, but mobile checks on the SS131 and the DCN are frequent. Limits change often: watch the signs.
Cabras is famous for muggine (grey mullet) from its lagoon and for bottarga, the cured roe. Grate it over spaghetti or eat it sliced with oil. On a Monday, try:
Il Caminetto and Sa Bell’e Crabasa are closed on Mondays. Phone ahead: off-season hours change.
A concrete car park for 142 cars. The paid season ends on 2 Nov, so today you still pay. Pay in the ParkingMyCar app or at the machine.
Cost: €4 up to 2 h
Navigate here ↗Pin39.95316, 8.40314
A beach made of polished quartz grains the size of rice, in white, pink and green. Taking any home is illegal and fined heavily, so photos only. Walk to both ends.
Optional, if you’re ahead: Mari Ermi next door is wilder and its parking is already free (39.96937, 8.40044). Take the paved way (≈ 15 km, 30 min: SP59 → SP7 → Strada Comunale Mari Ermi), not the 3.5 km dirt track.

The paved car park closest to Tharros. There are more just north (39.88235, 8.43900 and 39.88380, 8.43856). It’s paid until 2 Nov; from 20:00 it’s free.
Cost: ≈ €3 up to 2 h, €5 up to 4 h
Navigate here ↗Pin39.87972, 8.43940
A long, narrow cape with sea on both sides, the Punic-Roman city of Tharros on the east shore, two Spanish towers and a nuraghe on the high point. The sun sets straight into the open sea.

Zia Belledda (from 20:00) or Leopardi (from 19:45); both are open on Monday evenings. Groceries for tomorrow’s picnic: Vicino a te, Via Tharros 121 (daily 07:30–21:00, OSM hours).
Skip Is Arutas and go straight to San Giovanni di Sinis by 16:00. Or skip the cape and watch the sunset from Is Arutas.
Drive the slow, scenic way over Monte Ferru past the Sos Molinos waterfall instead of the SS131 (+30–40 min).
Almost everything indoors is shut on Mondays, including the Cabras museum and Tharros. Before you leave the east, do the 11:00 tour at the Grotta di Ispinigoli (no closing day listed; phone +39 348 478 0104 to check the road), then drive to Oristano and wander its old centre and cathedral.