The small town of Karavostasi has the only port (ferry boats) in the island. It is by no means touristy and you can a quiet stay in a typical "Cycladic" environment.
Moor: can pass on both sides of the islets Dyo Adelphia in the middle of the entrance to the bay. Leave the outer third of the ferry pier free.
The bay is also suitable for anchoring.
Don't miss: Take the bus to visit the Chora