Ios or Kefalonia?

The two are close on beaches, but the beaches feel quite different. Ios is a sand island: Mylopotas is the long social bay with sunbeds and water sports, Manganari's sheltered coves in the south have shallow, clear water, and the east and north coasts have emptier bays reached by rough road. The meltemi wind can churn the north-facing bays, so the south coast is the fallback.

Kefalonia offers more variety and more scenery, with Myrtos's white pebble beneath tall cliffs, Petani on the Paliki peninsula, red-sand Xi and long sandy stretches at Skala and Lourdas. The sea is a touch warmer and very clear, but the best beaches lie on different coasts, so beach days often mean driving.

Kefalonia eats noticeably better. It has dishes of its own, including the spiced meat pie, bourbourelia bean soup and aliada garlic sauce with salt cod, plus Robola white wine from the Omala valley wineries and a fish market on the Argostoli waterfront. Menus do repeat outside the main resorts, though.

Ios has grilled octopus at Yialos harbour and its own skotyri cheese, and a few kitchens in Chora cook with care. In high summer, though, much of the island feeds a late-night crowd with gyros and pizza, so a good meal takes some searching.

Neither island is a reason to travel for sights, and they are about level. The difference is that Ios's main attraction is intact: Chora is a whole Cycladic village of whitewashed lanes, blue domes and windmills, with the Early Cycladic walls at Skarkos and the legendary tomb of Homer nearby.

Kefalonia lost almost all its old towns to the 1953 earthquake, so its culture comes as scattered outings by car. These include Venetian Fiskardo, the fortress at Assos, the Mycenaean tomb at Tzanata, the Monastery of Agios Gerasimos and abandoned Old Vlachata.

This is where the islands differ most. Ios has been one of the Aegean's great party islands for decades, and in July and August dozens of bars and a few clubs fill Chora's lanes and square until dawn, with beach parties at Mylopotas starting the evening early. It is young and loud, built on cheap drinks rather than cocktails.

Kefalonia's evenings are long dinners and a drink by the harbour. Argostoli's Lithostroto and the bars at Lassi stay busy late in summer, but clubs are few, and partygoers will be disappointed.

Kefalonia is far greener and wilder. Mount Ainos rises above 1,600m in a national park of dark Greek fir with semi-wild horses, the west coast falls in white cliffs, and the karst hides the Melissani lake cave and the Drogarati stalactite chamber. There are also loggerhead turtles, sea kayaking and sailing towards Ithaca.

Ios is bare and rocky, with terraced hills, old mule tracks to remote chapels and boat trips to sea caves. It is pleasant walking country in spring, but it has nothing like Kefalonia's forest or wildlife.

Ios is better placed for days out. It sits in the middle of the Cyclades, Santorini's caldera villages and Akrotiri are an hour or less by fast boat, and Naxos, Sikinos and Folegandros are within reach. All of this depends on summer ferry timetables.

Kefalonia's best outing is Ithaca, a short crossing from Sami, with Zakynthos and Lefkada reachable in season. Beyond those, the island itself provides the excursions, since Fiskardo, Assos and Paliki each make a full day from a southern base.

Kefalonia works better for children. The gently shelving sand at Skala, Lourdas and Xi suits small swimmers, and the Melissani boat ride and turtle-spotting give some variety. The catch is long, hot drives between sights.

Ios has shallow coves at Manganari and the quieter end of Mylopotas. However, Chora's steep steps defeat a pushchair, and in high summer the party noise carries late, so families should come in June or September and stay in the south.

Ios is easier to manage once you arrive, though arriving takes a ferry because it has no airport. The harbour at Yialos, Chora and Mylopotas form a compact triangle served by a frequent summer bus and an old stepped path, so a car is only needed for the remote eastern and northern bays.

Kefalonia is large and mountainous, and a hired car is close to essential. Fiskardo is about an hour and a half's drive from Argostoli on winding roads, buses are too rare to plan around, and parking at Myrtos and Assos is tight in summer.

Neither island is for shopping. Ios's Chora has beachwear, sandals, jewellery and a few boutiques with Greek-made clothes and ceramics, open late for the evening crowd. Kefalonia's best buys are edible: Robola wine, thyme honey, olive oil and red mandoles almonds, along with the everyday shops of Argostoli's Lithostroto and craft stalls in Fiskardo.

Ios is slightly easier on a budget, thanks to its backpacker history: hostels, campsites, simple rooms and cheap bar food are still easy to find, although ferry fares add up. Kefalonia is middling for an island in summer. Taverna meals and rooms in the south are fair value, but Fiskardo and Assos are expensive and nearly everyone pays for car hire. On both islands, June and September cost less than high summer.

There is little on either island, but Kefalonia has more of a musical tradition. Its kantades serenades and Argostoli's philharmonic band, a tradition since the nineteenth century, turn up at village festivals and summer concerts in the squares. On Ios the music comes from the bars, apart from occasional events at the open-air theatre by the windmills.

Kefalonia is the more restful island. There are spas at the larger resort hotels, but the real draw is the pace: slow lunches in hill villages, quiet evenings at the harbours of Assos and Fiskardo, and the calm Paliki peninsula.

Ios can be peaceful in June or September or near Manganari, and a few boutique hotels offer yoga and massage. In high summer, though, its rhythm is late nights and late mornings.