Serifos is connected daily with the port of Piraeus through line Kithnos - Serifos - Sifnos - Milos. The trip by ferry lasts about 4 hours, while by the high speed about 2,5 hours.
From Serifos you can go to other Cyclades islands. There are routes all year around to: Ios, Kimolos, Santorini, Paros, Folegandros, Tinos and Syros.
For more information:
PORT AUTHORITIES OF PIRAEUS 210 4226000
PORT AUTHORITIES OF SERIFOS 22810 51470