Mykonos and Santorini have DAILY ferry connections.
The island is connected from Pireaus port (20 minutes metro ride from Athens down town). There are two types of ferries: the normal ones ( Blue star ferries) that take around 7 hours (cost 40 € one way) and the fast ones that take around 4 hours and are more expensive ( cost 60 € one way).
The island is connected daily from Pireaus and Rafina port ( 2 ports). If you overnight in Athens, Pireaus port is much closer than Rafina port and we recommend you to book your ferry from Pireaus.
a. Pireaus port:
Pireaus has frequent schedules for Mykonos and it is much closer to the center of Athens ( 20 minutes metro ride).From Pireaus port there are normal ferries that take around 5 hours (cost 35 € one way) and fast ferries that take around 3 hours (cost 50 € one way).
b. Rafina port:
The connection via Rafina is always shorter and cheaper than Pireaus and the port is closer to the Athens airport. If you are in Athens there are regular buses that take 1:30 to reach the port and cost around 5 €.
If you want to book your ferries to the Greek islands please use our trustworthy partner: www.greekferries.gr