Sikinos and Folegandros are neighbours on the south-western edge of the Cyclades, two small, steep islands with clifftop villages and a fraction of the visitors that Santorini or Ios receive. Folegandros is the better known of the pair, with a striking Chora perched above the sea; Sikinos is quieter still. Hopping from one to the other is a natural way to combine two slow-paced islands in a single trip.
The crossing is short enough to be almost an afterthought. Ferryhopper lists 25 minutes as the quickest trip in this direction, and most sailings take about 40 to 45 minutes. It is also cheap: fares started at €4 for one adult when we checked, on Fast Ferries. What makes it worth a little planning is the timetable, because no single company sails every day.
Three companies cover the route through the year. Fast Ferries sails 3 or 4 days a week in last year's data, Blue Star Ferries 2 or 3 days, and the local Maistros Santorini boat 1 to 3 days. Put together, that gives boats 6 to 7 days a week, but often only one sailing on a given day. Seajets turned up just once a week in a single month last year, and its sailing took a surprising 2 hours, so it is not the quick option its name suggests.
Before booking, check which boat runs on your date and what time it leaves Alopronia, Sikinos's port. On Folegandros you arrive at Karavostasis, below Chora, so arrange the ride up to your room in advance if you land late in the day.
