I want to go to Thira and Ios at the end of May, but I am not sure if I should buy the ferry tickets now or just wait till I am in Athens and by them the day before I want to leave. Do the ferries sell out quick? I was thinking about an overnight ferry to Thira with a deck ticket. Has anyone done a long overnight voyage on the deck? How was it?
i doubt you'll have a problem finding tickets at the last moment.
travelling by ferry to Thira on deck are quite "easy" from athens. i think that you can talk a ferry to Crete (which makes a stop at Thira).
i think it's 5-6 hours from athens to thira but keep in mind that this ferry leaves port at 21:00 and arrives at Thira at 03:00.
u c an take a closer look here :
Ferries to Thira