Island ferries: book the fast ones ahead, bring patience for the slow ones

Ferry schedules are published in spring and the fast catamarans to Mykonos and Santorini sell out in July and August, so book those a few weeks ahead on a ferry-comparison site. The big conventional ferries are cheaper, steadier in wind, and rarely full; a deck seat is fine for daytime. Strong summer winds (the "meltemi") cancel the small boats, so avoid booking a flight home for the same day as an island crossing.