Lefkada or Mykonos?

These are two of Greece's strongest beach islands, and the difference is in character rather than quality. Lefkada's showpieces are on the west coast, at Porto Katsiki, Egremni and Kathisma: long strands under white cliffs with startling turquoise water, but steeply shelving, wavy in the afternoon and sometimes reached by long staircases. Its calm swimming is on the east side, in the bays around Nikiana and Ligia.

Mykonos offers sandier, more organised south-coast bays, from sheltered Ornos and polished Psarou to the party beaches of Paradise and Super Paradise, many lined with sunbeds and beach clubs. When the meltemi blows, its wilder north coast is for still days only.

Mykonos eats a little better and more variously. Its own specialities, the peppery kopanisti cheese, louza and Chora's almond sweets, sit alongside a large high-end scene of sushi, fusion and celebrity-chef tables, though that scene is often more about being seen than eating well.

Lefkada stays with the Greek taverna: harbour fish in Lefkada town and Nidri, slow-cooked meat in mountain villages such as Karya, and the small lentils of the Eglouvi plateau. It is honest and simple, with little beyond Greek food.

Mykonos has far more to see. Delos alone, with the Terrace of the Lions, mosaic-floored houses and theatres spread across the sacred island of Apollo, deserves a full morning. Back in Chora, the windmills at Kato Mili, the Paraportiani church and a handful of small museums fill another day or two.

Lefkada's sights are pleasant breaks from the beach rather than reasons to come: the Santa Maura fortress at the causeway, the Faneromeni monastery above the lagoon, the painted Ionian church ceilings in town and the embroidery tradition of Karya.

This is the widest gap between them. Mykonos is one of the Mediterranean's great party islands, with beach-club afternoons, dance bars in Chora's lanes, a long-established gay scene and big clubs with international DJs that run until sunrise through July and August.

Lefkada's evenings are a drink and a stroll: cocktail bars in the town's lanes full of young Greek visitors, sailing crews on Nidri's harbour and windsurfers in Vasiliki's relaxed bars. There is no clubbing to speak of, and outside high summer the island goes to bed early.

Lefkada is much the better island for outdoor time. Olive and cypress slopes rise to an interior above 1,100m, paths link hill villages and lead to the Dimosari waterfall, and the cliff road to Cape Lefkatas is spectacular. On the water, Vasiliki is a famous windsurfing bay and the channels towards Meganisi are classic sailing country.

Mykonos is low, brown and rocky, beautiful for its light rather than its landscape. It has the meltemi for kitesurfing at Korfos Bay, though, and clear water with reefs and wrecks that suits divers and snorkellers better than Lefkada does.

Both make good bases for excursions, but of different kinds. From Lefkada you can mix islands and mainland: the fishing villages of Meganisi, Fiskardo on Kefalonia and Ithaca by ferry, or a drive to Roman Nikopolis and Venetian Parga.

From Mykonos every outing is island-hopping in the Cyclades: pilgrim Tinos with its marble-carving villages, neoclassical Ermoupoli on Syros, and Paros or Naxos by fast boat. The variety is narrower, and the meltemi can disrupt crossings.

Lefkada is the easier family island. The east-coast bays around Nikiana and Ligia, plus Agiofili and Vasiliki in the south, have calm water for paddling, and the island's evenings are relaxed enough for children. The dramatic west coast is best kept for an occasional day out.

Mykonos can work if you pick Agios Stefanos, Ornos or Platis Gialos, and the water park near Elia and the ruins on Delos help with older children. But the island is built around adult nights out, and Chora gets loud and crowded late in summer.

Mykonos is somewhat simpler to move around. The island is small, Chora is entirely car-free, buses serve the main south-coast beaches and sea taxis hop between bays from Platis Gialos and Ornos. Its weak spots are the scarcity of taxis in summer and the congested roads around town.

Lefkada needs no ferry, thanks to its causeway, and Aktion airport is about half an hour away. Once there, though, a car or scooter is close to essential, the mountain and west-coast roads are slow and winding, and Nidri and Porto Katsiki jam up in August.

Mykonos is the better place to shop, if what you want is a beach wardrobe. Matoyianni Street and the lanes around it are full of designer resort wear, linen, sandals, fine Greek jewellery and galleries that stay open late, though much of it closes outside the season.

Lefkada's shopping is an evening stroll down the town's pedestrian main street for olive oil, honey and lentils, plus hand embroidery in Karya. That is a modest list, but these are local crafts that Mykonos does not have.

The price gap is large. Lefkada sits mid-range for a Greek island, with plenty of family-run studios, reasonable tavernas and few entry fees. The main costs are August rooms near the west-coast beaches, car hire and boat trips.

In season Mykonos ranks among Europe's most expensive destinations, with hotels far above Greek norms and beach clubs, sunbeds and cocktails priced for a luxury crowd. Rooms at Ano Mera, the buses and Chora's bakeries soften the bill, and on both islands June and September bring easier prices.

Neither island is a place for theatre or concerts, but Lefkada has a little more. Its international folklore festival has filled open-air stages with dance groups every August for decades, and summer brings village festivals with traditional music. On Mykonos the music is mostly the DJ sets of its clubs, with only the occasional concert or village festival.

Neither island has a bathing tradition, and both are restful only away from their busiest corners. Mykonos offers pampering in upmarket hotel spas with yoga on sea-facing terraces, and quiet around Agios Sostis and Ftelia.

Lefkada's calm is more rural and spread across the island: yoga and retreat stays in the hills, quiet interior villages and slow evenings in the east-coast harbours, best in June or September.