Outside Ermoupoli, Syros comprises a series of hills and valleys folding down to small bays and beaches, most well served by buses.
Kini, on the west coast, is a sandy beach in a horseshoe bay with a small strip of bars and tavernas. It's popular with families due to its shallow waters.
Popular with French travellers, Galissas has an appealing beach, a smattering of white-and-blue-trim Cycladic buildings, some good tavernas and a cute little white church on the headland. On the other side of the church is Armeos, a pretty little pebbly nudist beach.
Further south, Finikas sits on a large bay with a marina at one end and a narrow strip of pebbles and sand. It's more built up than most of the others, with a somewhat shabby feel. Further along the bay is Voulgari Beach, near the village of Posidonia. South of the headland is tiny but popular Agathopes beach, with calm waters and a taverna. Another 10-minute walk south brings you to Komito, a sheltered bay backed by olive groves.
The south-coast town of Megas Gialos has a couple of beaches hard up against the main road. Gorgeous (and sheltered) Vari, further east, is the better bet with its sandy beach, though the waterfront and tavernas get packed with families in high season.