Ios or Peloponnese?

The two are evenly matched on beaches, and both are sand-led. Ios packs its beach life into a small island: the long social bay at Mylopotas with sunbeds and water sports, and the clear, shallow coves of Manganari in the south when the meltemi blows up the north side.

The Peloponnese offers range rather than concentration, spread over hours of driving: the horseshoe of Voidokilia and the Messinian sands, the pale turquoise water of Elafonisos, pebble coves below Mani villages and easy family beaches at Tolo. Its water is a touch warmer in late summer, and outside the peak months many beaches are close to empty.

The mainland eats far better. The Peloponnese cooks from its own land, with Kalamata olives and oil, slow-cooked goat, Mani cured pork and wild greens, and it makes serious wine in Nemea, on the Tripoli plateau and at Monemvasia. Kalamata's covered market and the tables of Nafplio give a town-sized choice.

Ios has a few careful tavernas in Chora and Yialos and its own skotyri cheese, but in summer many kitchens are feeding the night crowd with gyros and pizza. Good meals there have to be hunted down.

This is the widest gap between the two. The Peloponnese holds a large share of ancient and medieval Greece: Mycenae and Tiryns, the theatre of Epidaurus, Olympia, Messene, Bassae, and then Byzantine Mystras, the rock of Monemvasia and the Venetian fortresses of Nafplio and Methoni. A week barely covers it.

On Ios the whitewashed village of Chora is itself the main sight, with the Early Cycladic walls at Skarkos, the small museum and the legendary tomb of Homer adding an afternoon at most.

Ios wins this outright, and for many visitors it is the reason to go. Its summer nights fill the lanes and square of Chora with young crowds moving between small bars and clubs until dawn, with afternoon beach parties at Mylopotas beforehand. It is loud and cheap rather than stylish, and it falls silent outside June to September.

In the Peloponnese the evening usually means dinner and a drink on Nafplio's waterfront or Kalamata's seafront. Only Patras, a university city on the north coast, has a club scene, and it is far from the beaches and ancient sites.

The Peloponnese has the landscape for an outdoors trip: Taygetos rising to about 2,400m, the Lousios gorge with its cliff monasteries, the long Menalon Trail, the rack railway through the Vouraikos gorge and the stark Mani walking down to Cape Tainaron. Add birdwatching at the Gialova lagoon and sea kayaking.

Ios is handsome in a bare, rocky way, with mule tracks to chapels and windmills, boat trips to sea caves and windsurfing at Mylopotas, but it is good for a morning's walk rather than a whole trip.

Ios relies on the ferry, which makes Santorini and its Akrotiri excavations an easy hop and Naxos, Sikinos or Folegandros good outings in high summer. Outside summer, same-day returns become uncertain.

The Peloponnese gives more choice and does not depend on timetables, provided you drive: Hydra and Spetses from the Argolid ports, Nemea's wineries, Athens about two hours away, the old towns of Pylos and Methoni, Monemvasia, Elafonisos and the Arcadian villages.

The Peloponnese is the easier family choice. It has shallow sandy bays at Tolo, in Messinia and on Elafonisos, resort hotels with kids' clubs, welcoming tavernas and ancient sites that older children can enjoy early in the day, though long car journeys come with it.

Ios can manage a beach week at Manganari in June or September, but Chora's steep steps defeat a pushchair, there is nothing aimed at children, and in July and August the party noise carries late.

Neither is especially easy, but in different ways. Ios is reached only by ferry, yet once there the harbour, Chora and Mylopotas form a small triangle served by a frequent summer bus and an old stepped path, so a carless stay works if you stick to it; the far bays need a scooter or car.

The Peloponnese is car country from the start. Motorways make the main towns quick, but mountain and Mani roads are slow, buses rarely reach sites or beaches, and only compact Nafplio and the old towns are pleasant on foot.

Neither is a shopping destination, but the Peloponnese gives you more to bring home: jewellery and ceramics in Nafplio's lanes, olive oil, honey and herbs, wine straight from Nemea's wineries and lively weekly markets in Kalamata and Tripoli. On Ios shopping comes down to beachwear, sandals and souvenirs in Chora's late-opening shops, with a handful of boutiques.

Both come in cheaper than the glamorous Cycladic islands, and the mainland goes a little further. The Peloponnese rewards travellers with village rooms in the Mani and Arcadia, taverna meals and local wine, though a hire car and site fees are hard to avoid.

Ios keeps its backpacker side, with hostels, campsites, grill food and bar offers, but rooms of any comfort, the quiet-bay boutique hotels and ferry fares add up in high summer. On both, June and September give the same sea for less.

The Peloponnese has one experience Ios cannot match: ancient drama at night in the theatre of Epidaurus during its long-running summer festival, with concerts at the Little Theatre nearby and a dance festival in Kalamata. Ios has occasional summer events at the open-air theatre by the windmills and saints'-day village music, but the island's soundtrack is its bars.

For rest, the Peloponnese is the better bet. Its slow stone villages and empty coves are restful in themselves, and it adds thermal springs at Loutraki and Methana, the warm sulphur lake at Kaiafas and full resort spas in Messinia.

Ios is built for late nights in high summer. It can be calm at Manganari or in June and September, with some hotel massage and yoga, but anyone wanting quiet has to plan around the island's main purpose.