The most common mistake in Greek island travel is arithmetic. Travellers count the islands they have heard of, divide their holiday by that number, and end up with an itinerary that allots a day and a half to places that deserve a week. The result is a trip spent largely in ports and on ferries, glimpsing islands rather than experiencing them. It is entirely avoidable.

The two-night minimum rule

Treat two nights as the absolute floor for any island, and three as the realistic minimum for enjoyment. The reasoning is simple: arrival and departure days are half-days at best once transfers and check-ins are done. With two nights, you get one full day. With three, you get two — enough to see something properly and still sit by the water doing nothing, which is, after all, half the point of Greece.

How many islands fit in your holiday?

A working formula that has served our travellers well:

• 7 days: two islands, or one island plus Athens.
• 10 days: two to three islands.
• 14 days: three to four islands, with one longer “anchor” stay.

If a draft itinerary exceeds these numbers, something will suffer — usually your patience. The islands you skip are not lost; they are the reason to come back.

Choose a group, not a wishlist

Greece has well over two hundred inhabited islands arranged in distinct groups — Cyclades, Dodecanese, Ionian, Sporades, Saronic and more. Ferry connections are dense within a group and sparse between groups. An itinerary that mixes groups often spends a full day repositioning through Athens.

The practical advice: pick one group per trip and explore it properly. Each has a different character — the Cyclades are sculptural and windswept, the Ionian green and gentle, the Dodecanese layered with history — so the choice of group is really a choice of mood.

Respect the ferries — and have a plan B

Ferries are part of the pleasure of Greek travel, but they reward respect. High-season boats fill up, summer winds occasionally cancel fast catamarans, and timetables firm up closer to the season than international travellers expect. Three rules keep you safe:

• Never book a ferry on the same day as an international flight. Spend the last night near your departure airport.
• Prefer morning crossings; if one is cancelled, the day still has options.
• On windy routes, conventional ferries sail in conditions that keep catamarans in port.

Build in an anchor stay

The best island itineraries are asymmetrical: shorter stays for exploring, plus one longer stay — four or five nights — where you unpack properly, learn the beach, find your taverna and stop checking the time. This anchor stay is what transforms a tour into a holiday. Place it second or last, when you have earned the slowdown.

Timing changes everything

June and September offer the islands at their best balance of warmth and calm; July and August bring heat, energy and full ferries; May and October trade swimming temperatures for near-private harbours. There is no wrong answer, but there are wrong expectations — know which version of the islands you are booking.

Mix island sizes deliberately

A subtler principle that separates good routes from great ones: vary the scale of the islands themselves. Large islands offer infrastructure, variety and rainy-day options; small islands offer intimacy and the feeling of having a place almost to yourself. Two large islands back to back can feel like two versions of the same trip; a large island followed by a small one feels like two different holidays. As a pattern, anchor on a larger island and contrast with a smaller neighbour — the change of scale does as much for the journey as the change of scenery.

Accommodation rhythm matters too

Pack-and-move trips punish heavy luggage and reward simple accommodation logic. Book places with flexible check-in where ferry timings are involved, favour locations within walking distance of the port on short stays (taxis on small islands are few and ferry arrivals create queues), and save the special, remote, view-of-a-lifetime accommodation for your anchor island, where you will actually be present to enjoy it. A spectacular suite used for eleven waking hours is a poor trade against a comfortable room used for three days.

Shoulder-season islands are a different country

One final encouragement: the islands in late May or early October are not a lesser version of the summer islands but a different and arguably finer place — locals unhurried, paths empty, the light long and golden. Some seasonal businesses will be closed, and swimming in May asks for mild bravery. But travellers whose image of Greece was formed by August crowds routinely describe a shoulder-season visit as the trip where they finally saw the country. If your dates are free, consider it seriously.

Or let the route come to you

One elegant alternative deserves mention: seeing the islands by small ship. A small-ship cruise removes the ferry logistics entirely — you unpack once and the islands arrive each morning. It suits travellers who want breadth without the packing and repacking.

However you travel, the principle is the same: fewer places, experienced properly, beat many places glimpsed. If you would like help shaping a route — by ferry, by ship, or a combination — the Eightarrows Travel team plans Greek journeys at exactly this pace.