What you're actually choosing between
"Which Greek island should I visit" is usually the wrong first question. Greece's islands are organized into geographic groups — the Greek National Tourism Organisation lists Argosaronic, Crete, Cyclades, Dodecanese, Evia, Ionian, North Aegean and Sporades as the main clusters — and ferry networks are built around connections within a group, not smoothly between groups. Choosing a group first, then picking specific islands inside it, keeps your transport simple. Choosing islands from two or three different groups for a one-week trip usually means routing back through Piraeus's ferry gates or another hub port, burning a day or more of your trip on transfers rather than time on an island.
Cyclades: the postcard image, and the most crowded
The Cyclades are the group most people picture when they imagine a Greek island: white-washed cube houses, blue-domed churches, and islands including Santorini, Mykonos, Naxos, Paros and Milos. They sit in the central Aegean, southeast of Athens, and are generally the best-connected group to Piraeus by ferry, with frequent departures especially in high season.
This is also the most heavily visited group, and Santorini and Mykonos in particular see substantial crowding and higher prices in peak summer months. Choosing a quieter Cycladic island — Naxos, Sifnos or Folegandros, for instance — over the two best-known names gets you a genuinely different, calmer experience while staying within the same well-connected ferry network.
Dodecanese: further out, closer to Turkey, more layered history
The Dodecanese sit further southeast, closer to the Turkish coast than to mainland Greece, and include Rhodes, Kos, Patmos, Symi and Karpathos. Because of this distance, ferry journeys from Piraeus to the Dodecanese generally take longer than to the Cyclades, and flying into Rhodes or Kos directly is a common alternative to a long ferry trip for visitors with limited time.
The group's history — passing through Byzantine, Ottoman, and a period of Italian administration in the early twentieth century before joining Greece after the Second World War — shows up in the architecture more visibly here than in most other island groups, particularly in Rhodes's walled medieval old town and Kos's Italian-era public buildings.
Ionian Islands: a different sea, a different feel
The Ionian islands — Corfu, Zakynthos, Kefalonia, Lefkada and Ithaca among them — sit on Greece's west coast, facing Italy and the Ionian Sea rather than the Aegean. This is easy to overlook if you're planning based on "Greek islands" as one category, but it has real practical consequences: Ionian islands are generally not reached by ferry from Piraeus at all, and are instead accessed via ports on Greece's western mainland (such as Patra or Igoumenitsa) or by direct flights, particularly to Corfu and Kefalonia.
The islands themselves also read differently, shaped by centuries under Venetian rather than Ottoman rule, with greener landscapes, a different architectural character, and — because they face west rather than into the Aegean — noticeably different weather patterns, including higher rainfall in the cooler months than the drier Cyclades or Dodecanese.
Saronic (Argosaronic): the closest group, and the one you can actually day-trip
The Saronic, or Argosaronic, islands — Aegina, Poros, Hydra, Spetses and Salamina — sit closest to Athens of any group and are the only cluster realistically visited as a day trip from the capital, since some connections take well under two hours by fast ferry. Hydra in particular is known for banning motor vehicles entirely, making it a distinctly quiet, walkable island despite being one of the more visited in the group.
For a short trip where you don't want to give up more than a day or two of your Athens time to island travel, the Saronic islands are usually the most efficient option, even though they're less dramatic scenically than the Cyclades.
Side by side
| Group | Best for | Trade-off |
|---|---|---|
| Cyclades | Classic white-and-blue island scenery, strong ferry links from Piraeus | Most crowded and expensive in peak summer, especially Santorini and Mykonos |
| Dodecanese | Layered history, Rhodes's old town, proximity to Turkey | Longer travel time from Athens; flying is often more practical than the ferry |
| Ionian | Greener landscapes, Venetian-era architecture, west-coast weather | Not reachable from Piraeus; needs a different mainland port or a direct flight |
| Saronic (Argosaronic) | Day trips or short stays close to Athens | Less dramatic scenery than the Cyclades or Dodecanese |
Situations where the answer flips
A trip built around diving, hiking or a specific historical interest can override the general pattern above — the Dodecanese's medieval architecture or the Ionian's greener hiking trails might matter more to you than travel convenience. Similarly, if you're arriving by international flight directly into Rhodes, Kos, Corfu or another island airport rather than via Athens, the calculus around "closest to Piraeus" is irrelevant, and choosing the group nearest your actual arrival point makes more sense than defaulting to the Cyclades because it's the most famous.
Before you book a ferry
Confirm the specific route, season and operator for any ferry you're relying on, since schedules shrink significantly outside the June-to-September window and some smaller-island routes run only a few times a week, or not at all, in the off season. This guide does not cover Crete, Evia, the North Aegean or the Sporades in detail — each is a substantial destination in its own right and worth researching separately rather than folding into a single island-group comparison.