Ferry fm Athens to Mykonos

It depends on the type of boat and what you reserved for seats.

For the larger car ferries, (5 hours...so likely you will be on one of these) you will board when passenger traffic is allowed (they usually have been loading the cars and trucks) once on there may be luggage storage below or you take it with you. If you have a reserved seat, you go there, if only deck passage, find a comfortable spot. They will have some type of snack bar/restaurant maybe some other type of concession. Ride should be smooth to slight rocking. You can go out on the deck, there will be several stops before Mykonos, that is the most interesting part of the trip, going in and out of a port.

There are the faster, smaller, flying cats or jet boats. Still a snack bar, but not usually access to the deck. On those the ride can be smooth, unless weather is choppy, then they can be very rough.

Overall, think basic working vessel, not a cruise ship experience.

On arrival, collect your bags and exit, there will be about a hundred people trying to sell you tours or a room, somewhere in that crowd will be your driver holding up a sign.

Thank you! This is very helpful.
We are taking the 5PM ferry fm Athens 3rd week of Oct. Arriving late in Mykonos. Do you recommend taking earlier ferry? How much faster are the jet boats?

It would be my preference to go earlier, I like to get to a place with some daylight left, but it would likely mean leaving at about 7:00 in the morning.

The jet boats cut the trip to 2 and a half hours

You might also look at flying.

Rulaurencio, I don't know what your schedule is like but there's an 8am ferry departure from Rafina that gets to Mykonos arouns 12:30pm. There is a bus from Central Athens to Rafina and there is a bus you can take from the airport as well.