There is a daily air connection of Syros with the Eleftherios Venizelos airport and from the port of Piraeus, directly to Syros. The boat trip lasts 4 hours. There is also a possibility to fly to Mykonos and then take the boat to Syros (30 min. sail). Also daily sails and excursions to the nearby islands of Tinos and Mykonos.
Public transportation around the island is quite good, especially during summer. To rent a car is rather cheap (30-40 euros a day), cheaper a motorbike.