Mykonos or Peloponnese?

Both are strong beach destinations, with Mykonos slightly ahead. The real difference is in character. Mykonos packs its sandy bays along one south coast, from sheltered Ornos and Agios Ioannis to the sunbed rows of Psarou and the party beaches of Paradise and Super Paradise. Sea taxis link them, so you can try a different beach each day.

The Peloponnese spreads its beaches along a far longer coastline: the horseshoe of Voidokilia and Navarino Bay in Messinia, the pale sand of Elafonisos, and pebble coves under the Mani villages. These beaches are quieter and less organised, but far apart, so you pick one stretch of coast rather than sampling them all.

The Peloponnese eats better and more honestly. It has Kalamata olives and oil, slow-cooked goat and wild greens in village tavernas, and wine straight from the Agiorgitiko vineyards of Nemea and the Moschofilero country around Tripoli. Mykonos offers fine settings, with grilled octopus over the water in Little Venice and its own kopanisti cheese and louza pork. Much of its dining, though, is high-end and built for being seen, and everyday Greek food is a smaller part of it.

Mykonos has one great sight, the sacred island of Delos, a short boat ride from the old harbour. Add the windmills, Little Venice and the Paraportiani church in Chora, and most visitors have seen it all in two or three days.

The Peloponnese is in another league. Olympia, Mycenae, Epidaurus, Messene and Bassae cover the ancient world, and Mystras, Monemvasia and the Venetian castles at Methoni and Koroni cover the medieval one. It could fill a fortnight, though seeing it all means moving between bases such as Nafplio and the Messinian coast.

Mykonos is far ahead here. Summer nights start with afternoon beach-club sessions at Paradise and move on to cocktail and dance bars in Chora's lanes, shaped by a long-established gay scene. Large clubs then carry on until sunrise.

In the Peloponnese, an evening means a long dinner and a drink on the waterfront in Nafplio or Kalamata. Only Patras, a university city on the north coast, has real clubs, and it is away from the beaches and sites where most visitors stay.

The Peloponnese wins outright. Taygetos rises to about 2,400m above the Mani, the Lousios gorge links cliffside monasteries in Arcadia, and the Menalon Trail and the Vouraikos rack railway lead into the mountains. On the coast, the Gialova lagoon draws migrating birds.

Mykonos is low, rocky and brown, beautiful for its light and sea rather than its land. Its outdoor strengths are on the water: kitesurfing and windsurfing in the meltemi at Korfos and Kalafatis, and diving around reefs and wrecks.

Every outing from Mykonos is by boat: first Delos, then Tinos, Syros, Paros and Naxos. All are Cycladic islands, and the meltemi can cancel crossings. The Peloponnese offers more range. There are the car-free islands of Hydra and Spetses off the Argolid, the wine villages of Nemea, the mountain villages of Arcadia and Monemvasia, with Athens about two hours away, though almost every trip needs a car.

The Peloponnese is the easier family choice. It has shallow sandy bays at Tolo, along the Messinian coast and on Elafonisos, resort hotels with kids' clubs, and sites such as Mycenae and Olympia for older children. The cost is long hours in the car.

Mykonos can work at quiet south-coast bays such as Agios Stefanos or Ornos, and there is a water park near Elia. But the island is built around adult nights out, and Chora gets loud and crowded late in high summer.

Neither is simple without your own transport, and the problems differ. On Mykonos, nowhere is far, Chora is walkable, and buses and sea taxis reach the main south-coast beaches. The trouble is too few taxis and congested roads in July and August. The Peloponnese is a large region that needs a car throughout. Fast motorways link the towns, but mountain roads are slow and buses rarely reach sites or beaches.

Mykonos is the better place to shop, though only in one narrow way. Matoyianni Street and the lanes around it are full of resort wear, swimwear, Greek jewellery and galleries, open late into the evening. The Peloponnese has little beyond the small boutiques of Nafplio. Its best finds are things to eat and drink: Kalamata olive oil, mountain honey, wine bought at the wineries of Nemea, and the weekly markets in Kalamata and Tripoli.

The gap is wide. In summer, Mykonos is one of the most expensive places in Europe, with hotels, beach-club sunbeds and cocktails priced for a luxury crowd. Inland rooms and gyros only soften the bill.

The Peloponnese costs far less. Family-run rooms in the Mani and Arcadian villages, taverna meals and local wine are all good value. The main extra costs are a hire car, fuel and entry fees at the sites.

Neither is a destination for the stage, but the Peloponnese has one event worth planning a trip around. Ancient drama is performed on summer weekend nights in the theatre of Epidaurus, with concerts at the Little Theatre nearby and a dance festival in Kalamata in July. Mykonos has club DJs and the odd village festival or open-air concert, but nothing worth booking a trip for.

The Peloponnese is the better place for rest. It offers slow village afternoons, empty coves outside high season, old spa towns at Loutraki and Methana, and the warm springs that feed the lake at Kaiafas. On Mykonos, wellness means hotel spas and yoga terraces. Its late-night summer rhythm works against calm unless you stay near Agios Sostis, Ftelia or beyond Kalafatis, or come in early June or late September.