The Greek Islands offer more variety than any other Mediterranean destination. Over 6,000 islands and islets dot the Aegean and Ionian seas. Only 227 are inhabited. Each group of islands has its own architecture, cuisine, and traditions. The Cyclades are famous for white-washed houses and blue domes. The Ionian islands are green and lush. The Dodecanese have medieval castles and strong Italian influences. The Saronic islands are easy to reach from Athens. The best time to visit is May, June, September, or October. July and August bring crowds and high prices. A ferry ticket between islands costs 30 to 60 euros depending on distance. This guide covers five island groups to help you plan your Greek island adventure.

The Cyclades: 33 Inhabited Islands with 1,200 Kilometres of Coastline

The Cyclades form a circle around the sacred island of Delos. There are 33 inhabited islands in the group. Santorini is the most famous. It was shaped by a volcanic eruption in 1600 BCE. The caldera is 12 kilometres across. The cliffside village of Oia sits 150 metres above the sea. Mykonos has 40 beaches and operates 2 international airports. Paros has 120 kilometres of coastline and remains more affordable than its neighbours. Naxos is the largest Cycladic island at 428 square kilometres. Ferry connections between Cycladic islands run 2 to 5 times daily in summer. A high-speed ferry from Athens to Mykonos takes 2.5 hours and costs 55 euros (as of 2026). A meal for two with wine costs 35 to 50 euros in a taverna.

The Ionian Islands: 7 Main Islands with 1,500 Millimetres of Annual Rainfall

The Ionian Islands lie off the west coast of mainland Greece. They receive more rainfall than any other Greek islands. The landscape is green and forested. Corfu was ruled by Venice from 1386 to 1797. The Venetian influence is visible in the architecture of Corfu Town. The Old Town is a UNESCO World heritage site. Zakynthos has the famous Shipwreck Beach, accessible only by boat. A boat tour costs 30 euros per person (as of 2026). Kefalonia is the largest Ionian island at 781 square kilometres. The underground lake of Melissani was discovered in 1951. It is 40 metres deep and the water is 14 degrees Celsius year-round. Lefkada is connected to the mainland by a floating bridge. Its Porto Katsiki beach is consistently ranked among the best in Greece.

The Dodecanese: 26 Inhabited Islands with 1,000 Knights

The Dodecanese means 12 islands in Greek, though the group actually has 26 inhabited islands. Rhodes is the largest at 1,401 square kilometres. The medieval Old Town is a UNESCO World heritage site. The Palace of the Grand Master was built in the 14th century. It has 158 rooms. Entry costs 8 euros (as of 2026). Kos has the Asklepion, an ancient medical school built in 357 BC. It was one of the first teaching hospitals in history. Patmos is where St John wrote the Book of Revelation in 95 AD. The Monastery of St John was built in 1088. The island has 2,000 inhabitants. Symi is famous for its neoclassical houses painted in pastel colours. The harbour has 14 preserved mansions from the 19th century.

The Saronic Islands: 5 Islands 30 to 50 Kilometres from Athens

The Saronic Islands are the closest to Athens. Hydra is the most distinctive. It has no cars. Only donkeys and water taxis provide transport. The island has 300 inhabitants. The Hydra Museum archives date from 1770. The island’s port has 8 18th-century mansions. Spetses has 20 kilometres of coastline. The island banned cars in the 1980s. Horse-drawn carriages are the main transport. Aegina is the largest Saronic island at 87 square kilometres. The Temple of Aphaia was built in 490 BC. It has 24 columns still standing. Poros is actually 2 islands connected by a bridge. The small island of Agistri offers 6 sandy beaches. Ferry from Athens to Hydra takes 1.5 hours and costs 35 euros (as of 2026).

Crete: Greece’s Largest Island at 8,336 Square Kilometres

Crete is the largest Greek island at 8,336 square kilometres. It is 260 kilometres long and 60 kilometres wide at its broadest point. The island has 1,046 kilometres of coastline. The Minoan civilisation flourished here from 2700 to 1450 BC. The Palace of Knossos was first excavated in 1900. The palace covers 22,000 square metres. Samaria Gorge is 16 kilometres long. It is protected as a national park. The walk takes 4 to 7 hours. The gorge drops from 1,250 metres at the entrance to sea level at the exit. Crete produces 65 percent of Greece’s olive oil. The island has 30 million olive trees. The oldest olive tree in Crete is estimated at 3,000 years old. Chania Old Town has a Venetian harbour built in 1320. A meal of dakos, grilled fish, and local wine costs 20 to 25 euros per person (as of 2026).

Which group of Greek Islands calls to you: the white-washed Cyclades or the green Ionian isles? 🇬🇷

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