Ios or Naxos?

These two islands are equally strong for beaches, and both have fine sand rather than pebble. The difference is in the layout. On Ios, Mylopotas is the one big social beach, with sunbeds and water sports. Quieter swimming means a trip to the sheltered coves of Manganari in the far south or a rough drive to the empty bays in the east and north.

Naxos has a near-continuous chain of pale sand down its west coast, from Agios Prokopios and Agia Anna to the dune-backed beaches of Plaka and Alyko. The water stays shallow a long way out, and you can stay with the beach at your door. On windy meltemi days, Ios swimmers head for the south coast, while on Naxos the sheltered spots are Agios Georgios and the coves behind the headlands.

Naxos eats noticeably better because it grows its own food. Potatoes come from its valleys and graviera and arseniko cheeses from its hills, and kitron liqueur is distilled in Halki. The best meals are in the mountain villages of Halki, Filoti, Apiranthos and Koronos, or at the harbourfront fish tavernas in Chora.

Ios has good moments, such as grilled octopus in Yialos and the local skotyri cheese with rusks and tomato. In high summer, though, many of its kitchens switch to gyros and pizza for the crowd heading out at night. Neither island offers much beyond Greek cooking.

Naxos has far more history to explore. The marble Portara frames the harbour, and above it the Venetian kastro holds Catholic churches, mansions with coats of arms and Cycladic figurines. Inland are the Temple of Demeter near Sangri, the unfinished kouroi at Flerio and Apollonas, and Panagia Drosiani with its very early frescoes. Seeing them takes a few days of driving.

On Ios, the main sight is Chora itself, with its windmills and chapels. Beyond it are the Early Cycladic walls at Skarkos, the traditional tomb of Homer at Plakotos and the ruined castle at Paleokastro, which together make a pleasant few hours.

This is where Ios clearly wins. In summer, dozens of small bars and a few clubs fill Chora's old lanes and square, crowds drift between them until dawn, and the afternoon parties on Mylopotas carry on into the evening. The crowd is young, the drinks are cheap and the music is familiar, so the scene is loud rather than stylish.

On Naxos, an evening usually means a long dinner and then cocktails by Chora's harbour or a sunset drink at a beach bar in Agios Prokopios or Plaka. A couple of clubs stay open late, but most people are in bed well before the Ios crowd.

Naxos has more varied country to explore. Mount Zas rises to about 1,000m, and the climb to its summit cave gives views across the archipelago. Mule paths run through the olive groves of the Tragaea valley, and Mikri Vigla is one of the best kitesurfing spots in the Aegean.

Ios is barer and rockier, with terraced slopes and cliffs. Its old tracks lead to remote chapels and northern bays, and boat trips reach sea caves you cannot get to by road. It is pleasant for a morning's walk or a windsurf at Mylopotas, but it will not fill an outdoor week.

Both islands sit in the middle of the Cyclades, and both depend on ferries for days out. From Ios, the obvious trip is Santorini, an hour or less by fast boat, for the caldera villages and the Bronze Age town of Akrotiri. Quieter Sikinos and Folegandros make gentler outings.

From Naxos, it is under an hour to Paros, and the Small Cyclades make easy days among quiet harbours. Mykonos is the stepping stone to Delos. Naxos also has a full day's drive on its own island, through the hill villages to Apollonas.

Naxos is much easier with children. Its west-coast beaches shelve so gently that toddlers can paddle far out, Agios Georgios is a short walk from Chora and sheltered from the wind, and family-run studios and tavernas make children welcome.

Ios has suitable sand at Manganari and the quieter end of Mylopotas. However, Chora's steep steps defeat a pushchair, and in July and August the party noise carries late into the night, so families do best staying near the southern beaches outside the peak weeks. Neither island has attractions built for children.

Getting around is equally easy, or equally awkward, on the two islands. The difference is in how much of each you can reach without a car. On Ios, you arrive only by ferry. The harbour at Yialos, Chora and Mylopotas form a compact triangle, linked by a frequent summer bus and an old stepped path, so a beach-and-bars trip needs no wheels.

Naxos is larger, and its summer buses run along the west-coast beaches to Plaka and up to the main hill villages. The island's best sights are inland, though, so a hire car is more worthwhile there, even though the drive to Apollonas takes well over an hour.

Neither island is a shopping destination, but Naxos has more worth taking home. Most of it is edible: graviera, kitron liqueur, thyme honey from village co-operatives, plus weaving and marble work in Apiranthos and Halki. On Ios, shopping means beachwear, sandals, jewellery and souvenirs in Chora's lanes, open late for the evening crowd.

Costs are much the same on both islands, but the cheap options differ. Ios still caters for backpackers, with hostels, campsites and simple rooms near Mylopotas, cheap grill food and drinks offers in the bars. Comfortable rooms in high summer and the ferry fares to get there still add up.

Naxos keeps its prices down with family-run studios, village rooms, reasonably priced taverna meals and local buses. Beachfront rooms and hire cars cost more in August. On both islands, June and September give the same warm sea for less.

Neither island has a theatre or concert season, but Naxos has a little more to go to. Its summer festival brings concerts and theatre to a restored Venetian tower inland, there are small recitals in the kastro, and at the village panigyria the violin and lute play late into the night.

On Ios, the open-air Odysseas Elytis theatre by the windmills puts on the occasional summer event, and saints' day festivals bring traditional dancing. Otherwise, live music on Ios means the music in its bars.

Naxos is the more restful island. Outside August, its beach villages and mountain hamlets settle into a rhythm of swim, siesta and long dinner, and a stay in the hills around Halki or on the emptier southern beaches is properly unhurried. A few resort hotels and yoga retreats on the southwest coast offer treatments.

Ios in peak summer runs on late nights and late mornings. Calm is possible in June or September, at the boutique hotels with spas near Mylopotas or tucked away at Manganari, but only well away from Chora.