The hard part of planning Greece is not choosing an island. It is working out which islands are near each other, because that is what decides whether a route is a holiday or a series of ferry terminals. The islands are not scattered at random: they sit in groups, and each group has its own character, its own boats and its own reason to go. Every island below sits at its real position, and every one of them opens its guide.
The groups, and what each one is for
The grouping is the useful part. Islands in the same group are close to each other and are usually connected by boat, which means a route inside one group is easy and a route across two groups costs you a day. Choosing a group first, and the islands second, is the single decision that stops a Greek itinerary from turning into a series of ferry terminals.
- The Cyclades are the postcard: white villages, bare rock, hard light. They are also the busiest and the windiest. This is where Santorini, Mykonos, Paros, Naxos and Milos are, and the group most island-hopping routes are built from. See the Cyclades hopping route.
- The Dodecanese run down the Turkish coast: greener, more layered, more history you can walk into. Rhodes anchors them, with Kos, Patmos, Symi and Karpathos.
- The Ionian islands sit on the other side of the country, in a different sea, and look it: pine, cypress, softer light, more rain. Corfu, Kefalonia, Zakynthos, Lefkada, Paxos, Ithaca. They are not a ferry ride from the Cyclades, and treating them as one is the most common planning mistake in Greece.
- Crete is not really an island in the sense the others are. It is big enough to be its own trip, with its own mountains, its own airports at either end, and its own reasons to stay two weeks.
- The mainland is where the archaeology is: Athens, Delphi, Meteora, Nafplio, Thessaloniki. It is badly underrated by people who come only for the islands.
Why every line on the map starts in the same place
The dotted lines all leave from one dot, and that is not a simplification. Piraeus, the port of Athens, is where the great majority of Aegean sailings begin, which is why so many Greek trips start with a night in Athens whether or not the traveller planned one. Rafina and Lavrio serve parts of the Cyclades too, and choosing the right one of the three is the highest-leverage ferry decision you will make. That is all in the ferries guide, along with which boats run when, and what the wind does to them.
The practical consequence for a route is simple: islands that share a group are cheap to combine, and islands that do not are expensive to combine, in the only currency that matters on a short trip, which is days. The island-hopping guide is about exactly that arithmetic.
What this map is, and what it is not
It is a positional map. Every island sits at its real coordinates, so the distances and the neighbours are true, and the question it is built to answer - what is near what - is answered honestly. It is not a nautical chart, it does not draw coastlines, and it should not be used to navigate anything. For a route you can actually sail, start from the itineraries, which are built backwards from real sailings.