This ancient port at the head of the deep Golfo Aranci has remains of a pre-Christian necropolis and, at 11thC San Simplicio church, some Roman tombs. Atte, concubine of Nero, came from Olbia. With its airport, ferry to the mainland and situation as gateway to the Costa Smeralda, the town has smartened itself up. Undeveloped shoreline along the Gulf has dense woodland – through which a tiny branch railway crawls – much wildlife and millions of tortoises.