Halkidiki or Lefkada?

Both places are first-rate for the sea, but the swimming feels quite different. Halkidiki's shore is mostly pale sand or small pebble sloping gently into calm water, with pine forest behind. Kassandra has the organised beaches with sunbeds and bars, while Sithonia has granite coves at Kavourotrypes and Karydi.

Lefkada's best-known beaches are more dramatic and more demanding. Porto Katsiki, Egremni and Kathisma lie under white cliffs facing the open Ionian, where the shore drops steeply and the waves build in the afternoon. For calm water you go to the small east-coast bays around Nikiana and Ligia, or to Agiofili in the south.

Halkidiki eats a little better. Its fishing villages, such as Nikiti, Toroni and Ouranoupoli, cook grilled octopus and mussels for Greek visitors, and Athos wines, the vineyards above Neos Marmaras and pine honey give it local products worth seeking out. Thessaloniki, one of Greece's great food cities, is close enough for lunch.

Lefkada's cooking is honest taverna food, at its most traditional in the mountain villages around Karya. It has its own Eglouvi lentils and cured salami, but there is no food scene beyond that and no city nearby to fill the gap.

Neither is a sightseeing destination, but Halkidiki has the one sight that stands out: Mount Athos. Most visitors see its cliff-top monasteries from a cruise boat out of Ouranoupoli, since entry is limited to men with a permit. Olynthos, ancient Stagira and the Petralona cave add solid half-days.

Lefkada's sights are smaller in scale. There is the Santa Maura fortress at the causeway, the painted church ceilings and earthquake-proof timber houses of Lefkada town, and the Faneromeni monastery above the lagoon. They are pleasant breaks from the beach rather than reasons to go.

Halkidiki goes out harder. Kallithea on Kassandra has open-air clubs that run late, and Pefkohori and Hanioti have bar strips that fill after midnight, kept busy at weekends by young Greeks driving in from Thessaloniki.

Lefkada has no clubbing to speak of. Summer nights mean cocktail bars in the lanes of Lefkada town, sailing crews on Nidri's harbour front and windsurfers at Vasiliki's relaxed bars. Out of high summer, both places go quiet, Lefkada earlier.

Lefkada has the bolder landscape. Olive and cypress slopes climb to mountains over 1,100m, and white cliffs drop into the sea on the west coast. You can walk to the Dimosari waterfall or along paths between hill villages. On the water it is even stronger, with Vasiliki's steady afternoon winds for windsurfing and sheltered channels made for a week of sailing.

Halkidiki's best scenery is on Sithonia, where granite headlands, small islets and the wooded slopes of Mount Itamos meet the sea. Outdoor days there are mostly kayaking, snorkelling and boat trips to Diaporos lagoon, and the only serious hike is on Athos, open only to men with a permit.

Both places have plenty of days out, but they take you in different directions. From Halkidiki the big trip is to a city: Thessaloniki, with its Byzantine churches and waterfront, and beyond it the royal tombs at Vergina and ancient Pella. Ammouliani and Kavala are within reach from the Athos side.

Lefkada's day trips are mostly by boat. You can reach Meganisi, Kalamos and Kastos from Nidri, or Fiskardo and Ithaca from Vasiliki, and on the mainland there are the Roman ruins at Nikopolis and the Venetian town of Parga.

Halkidiki is the stronger family choice. Sandy beaches with long shallows on Kassandra and around Gerakini and Psakoudia, a usually calm sea and resorts with pools and children's clubs make the days easy, even without zoos or theme parks.

Lefkada can work for families, but only from the east side, around Nikiana, Ligia and Agiofili. Its famous west-coast beaches, with steep shelving, afternoon surf and long cliff staircases, are hard going with small children.

You need a car in both places, but the problems are different. On Halkidiki the peninsulas make every crossing a long loop back to the base and down the next one, and southern Sithonia is nearly two hours from Thessaloniki airport.

Lefkada is more compact, linked to the mainland by a causeway and about half an hour from Aktion airport. Its roads over the mountains and down the west coast are slow, though, and Nidri and the parking at Porto Katsiki jam in August.

Neither is a shopping destination, but Lefkada gives you a bit more to browse. The evening stroll down Lefkada town's pedestrian main street passes small clothing shops and jewellers, and Karya sells hand embroidery.

Halkidiki has mostly resort strips. The best things to take home are its olive oil, honey and wine, plus the icons and incense sold in Ouranoupoli at the edge of Athos.

Prices are much the same, mid-range for the Greek coast, and in both places June and September cost clearly less than August. Halkidiki has a deep supply of simple rooms because so many visitors are Greek and Balkan families driving in. On Lefkada the extra costs tend to be car hire, boat excursions and rooms near the famous west-coast beaches.

Both have little beyond summer, and what they offer is different. Halkidiki puts on concerts and theatre at the open-air amphitheatre at Siviri, plus jazz and classical evenings at the Sani Festival, with Thessaloniki's stages within reach. Lefkada's big event is a long-running international folklore festival every August, with dance groups on open-air stages in town.

Halkidiki gives you more for a restful stay. The thermal springs at Agia Paraskevi, on the southern tip of Kassandra, offer warm mineral pools above the sea, and the large resorts have proper spas. Sithonia and the coast towards Ouranoupoli are the calmest places to stay.

Lefkada has no bathing tradition and only a few spa hotels and hillside yoga stays. Its calm comes from the interior villages and the small east-coast harbours, best in June or September.