The choppy blue waters of the Golfo di Oristano provide a magnificent backdrop to the ruins of ancient Tharros. Founded by the Phoenicians in the 8th century BC, the city thrived as a Carthaginian naval base and was later taken over by the Romans. Much of what you see today dates to the 2nd and 3rd centuries AD, when the basalt streets were laid and the aqueduct, baths and other major monuments were built. As you approach the site it's impossible to see the ruins until you reach the hilltop ticket office. From here follow a brief stretch of cardo (the main street in a Roman settlement) until you reach, on your left, the castellum aquae, the city’s main water reserve. Two lines of pillars can be made out within the square structure. From here the Cardo Massimo, the city’s main thoroughfare, leads to a bare rise topped by a Carthaginian acropolis and a tophet, a sacred burial ground for children. Also here are remains of the original nuraghic settlement. From the bottom of the Cardo Massimo, the Decumano runs down to the sea passing the remains of a Punic temple and, beyond that, the Roman-era Tempio Tetrastilo, marked by its two solitary columns. These are, in fact, reconstructions, although the Corinthian capital balanced on the top of one is authentic. Nearby is a set of thermal baths and, to the north, the remains of a palaeo-Christian baptistry. At the southernmost point of the settlement is another set of baths, dating to the 3rd century AD. For a bird’s-eye view of the site, head up to the late-16th-century Torre di San Giovanni watchtower, occasionally used for exhibitions. Here you can look down on the ruins, as well as the Spiaggia di San Giovanni di Sinis, a popular beach that extends on both sides of the tower. You can also stroll down the dirt tracks to Capo San Marco and the lighthouse.