Undoubtedly the most extraordinary island in the Aegean, crescent-shape Santorini remains a mandatory stop on the Cycladic tourist route—even if it's necessary to enjoy the sensational sunsets from Ia, the fascinating excavations, and the dazzling white towns with a million other travelers. Called Kállisti (the "Loveliest") when first settled, the island has now reverted to its subsequent name of Thira, after the 9th-century-BC Dorian colonizer Thiras. The place is better known, however, these days as Santorini, a name derived from its patroness, St. Irene of Thessaloniki, the Byzantine empress who restored icons to Orthodoxy and died in 802. You can fly conveniently to Santorini, but to enjoy a true Santorini rite of passage, opt instead for the boat trip here, which provides a spectacular introduction. After the boat sails between Sikinos and Ios, your deck-side perch approaches two close islands with a passage between them. The bigger one on the left is Santorini, and the smaller on the right is Thirassia. Passing between them, you see the village of Ia adorning Santorini's northernmost cliff like a white geometric beehive. You are in the caldera (volcanic crater), one of the world's truly breathtaking sights: a demilune of cliffs rising 1,100 feet, with the white clusters of the towns of Fira and Ia perched along the top. The bay, once the high center of the island, is 1,300 feet in some places, so deep that when boats dock in Santorini's shabby little port of Athinios, they do not drop anchor. The encircling cliffs are the ancient rim of a still-active volcano, and you are sailing east across its flooded caldera. On your right are the Burnt isles, the White isle, and other volcanic remnants, all lined up as if some outsize display in a geology museum. Hephaestus's subterranean fires smolder still—the volcano erupted in 198 BC, about 735, and there was an earthquake in 1956. Indeed, Santorini and its four neighboring islets are the fragmentary remains of a larger landmass that exploded about 1600 BC: the volcano's core blew sky high, and the sea rushed into the abyss to create the great bay, which measures 10 km by 7 km (6 mi by 4½ mi) and is 1,292 feet deep. The other pieces of the rim, which broke off in later eruptions, are Thirassia, where a few hundred people live, and deserted little Aspronissi ("White isle"). In the center of the bay, black and uninhabited, two cones, the Burnt Isles of Palea Kameni and Nea Kameni, appeared between 1573 and 1925. There has been too much speculation about the identification of Santorini with the mythical Atlantis, mentioned in Egyptian papyri and by Plato (who says it's in the Atlantic), but myths are hard to pin down. This is not true of old arguments about whether tidal waves from Santorini's cataclysmic explosion destroyed Minoan civilization on Crete, 113 km (70 mi) away. The latest carbon-dating evidence, which points to a few years before 1600 BC for the eruption, clearly indicates that the Minoans outlasted the eruption by a couple of hundred years, but most probably in a weakened state. In fact, the island still endures hardships: since antiquity, Santorini has depended on rain collected in cisterns for drinking and irrigating—the well water is often brackish—and the serious shortage is alleviated by the importation of water. However, the volcanic soil also yields riches: small, intense tomatoes with tough skins used for tomato paste (good restaurants here serve them); the famous Santorini fava beans, which have a light, fresh taste; barley; wheat; and white-skin eggplants.

Although the fishing boats still go out in good weather, Mykonos largely makes its living from tourism these days. The summer crowds have turned one of the poorest islands in Greece into one of the richest. Old Mykonians complain that their young, who have inherited stores where their grandfathers once sold eggs or wine, get so much rent that they have lost ambition, and in summer sit around pool bars at night with their friends, and hang out in Athens in winter when island life is less scintillating. Put firmly on the map by Jackie O in the 1960s, Mykonos town—called Hora by the locals—remains the Saint-Tropez of the Greek islands. The scenery is memorable, with its whitewashed streets, Little Venice, the Kato Myli ridge of windmills, and Kastro, the town's medieval quarter. Its cubical two- or three-story houses and churches, with their red or blue doors and domes and wooden balconies, have been long celebrated as some of the best examples of classic Cycladic architecture. Luckily, the Greek Archaeological Service decided to preserve the town, even when the Mykonians would have preferred to rebuild, and so the Old Town has been impressively preserved. Pink oleander, scarlet hibiscus, and trailing green pepper trees form a contrast amid the dazzling whiteness, whose frequent renewal with whitewash is required by law. Any visitor who has the pleasure of getting lost in its narrow streets (made all the narrower by the many outdoor stone staircases, which maximize housing space in the crowded village) will appreciate how its confusing layout was designed to foil pirates—if it was designed at all. After Mykonos fell under Turkish rule in 1537, the Ottomans allowed the islanders to arm their vessels against pirates, which had a contradictory effect: many of them found that raiding other islands was more profitable than tilling arid land. At the height of Aegean piracy, Mykonos was the principal headquarters of the corsair fleets—the place where pirates met their fellows, found willing women, and filled out their crews. Eventually the illicit activity evolved into a legitimate and thriving trade network. Morning on Mykonos town's main quay is busy with deliveries, visitors for the Delos boats, lazy breakfasters, and street cleaners dealing with the previous night's mess. In late morning the cruise-boat people arrive, and the shops are all open. In early afternoon, shaded outdoor tavernas are full of diners eating salads (Mykonos's produce is mostly imported); music is absent or kept low. In mid- and late afternoon, the town feels sleepy, since so many people are at the beach, on excursions, or sleeping in their air-conditioned rooms; even some tourist shops close for siesta. By sunset, people have come back from the beach, having taken their showers and rested. At night, the atmosphere in Mykonos ramps up. The cruise-boat people are mostly gone, coughing three-wheelers make no deliveries in the narrow streets, and everyone is dressed sexy for summer and starting to shimmy with the scene. Many shops stay open past midnight, the restaurants fill up, and the bars and discos make ice cubes as fast as they can. Ready to dive in? Begin your tour of Mykonos town (Hora) by starting out at its heart: Mando Mavrogenous Square.

Naples, in the Campania region, is Italy's third largest city. Its claim to fame is the spectacular location along one of the world's most splendid bays, backed by the perfect cone of Mount Vesuvius. In addition to its beautiful setting, Naples' surprises with other outstanding attractions such as the Royal Palace, San Carlos Opera House, the impressive National Archaeological Museum and the Castel Nuovo, dating from the 13th-century. The city's central area is best explored on foot. Chaotic traffic conditions make driving around the city a very frustrating experience. Naples provides a convenient starting point for trips to such favored destinations as Pompeii, Herculaneum and Mount Vesuvius. The Isle of Capri can be reached via a 45-minute hydrofoil service. The region of Campania was home to Greeks settlers some 300 years before Rome was founded. Pompeii, too, was a Greek town before being conquered by the Romans during the 5th century BC. It was under the Romans that Pompeii flourished and grew prosperous. When Mount Vesuvius erupted in 79 AD, the population of 20,000 was wiped out, but dozens of buildings were preserved under layers of cinder more than 20 feet deep. The most important finds from Pompeii are displayed in Naples' National Archaeological Museum. A visit here will no doubt enhance a visit to ancient Pompeii.

Italy's vibrant capital lives in the present, but no other city on earth evokes its past so powerfully. For over 2,500 years, emperors, popes, artists, and common citizens have left their mark here. Archaeological remains from ancient Rome, art-stuffed churches, and the treasures of Vatican City vie for your attention, but Rome is also a wonderful place to practice the Italian-perfected il dolce far niente, the sweet art of idleness. Your most memorable experiences may include sitting at a caffè in the Campo de' Fiori or strolling in a beguiling piazza.

La Spezia is sometimes thought of as nothing but a large, industrialized naval port en route to the Cinque Terre and Portovenere, but it does possess some charm, and it gives you a look at a less tourist-focused part of the Riviera. Its palm-lined promenade, fertile citrus parks, renovated Liberty-style palazzos, and colorful balcony-lined streets make parts of La Spezia surprisingly beautiful. Monday through Saturday mornings, you can stroll through the fresh fish, produce, and local-cheese stalls at the outdoor market on Piazza Cavour, and on Friday take part in the busy flea market on Via Garibaldi. There's also Porto Mirabello, a newly built tourist port with a pool club, shops, and several restaurants that overlook the fleet of super-yachts.

La Spezia is sometimes thought of as nothing but a large, industrialized naval port en route to the Cinque Terre and Portovenere, but it does possess some charm, and it gives you a look at a less tourist-focused part of the Riviera. Its palm-lined promenade, fertile citrus parks, renovated Liberty-style palazzos, and colorful balcony-lined streets make parts of La Spezia surprisingly beautiful. Monday through Saturday mornings, you can stroll through the fresh fish, produce, and local-cheese stalls at the outdoor market on Piazza Cavour, and on Friday take part in the busy flea market on Via Garibaldi. There's also Porto Mirabello, a newly built tourist port with a pool club, shops, and several restaurants that overlook the fleet of super-yachts.

Villefranche-Sur-Mer is located on the Côte d’Azur in Provence – known for its fields of lavender and warm weather – and is highly appreciated for its 14th Century architecture.

If you look north of the cathedral (La Seu, or the seat of the bishopric, to Mallorcans) on a map of the city of Palma, you can see around the Plaça Santa Eulàlia a jumble of tiny streets that made up the earliest settlement. Farther out, a ring of wide boulevards traces the fortifications built by the Moors to defend the larger city that emerged by the 12th century. The zigzags mark the bastions that jutted out at regular intervals. By the end of the 19th century, most of the walls had been demolished; the only place where you can still see the massive defenses is at Ses Voltes, along the seafront west of the cathedral.A torrent (streambed) used to run through the middle of the old city, dry for most of the year but often a raging flood in the rainy season. In the 17th century it was diverted to the east, along the moat that ran outside the city walls. Two of Palma's main arteries, La Rambla and the Passeig d'es Born, now follow the stream's natural course. The traditional evening paseo (promenade) takes place on the Born.If you come to Palma by car, park in the garage beneath the Parc de la Mar (the ramp is just off the highway from the airport, as you reach the cathedral) and stroll along the park. Beside it run the huge bastions guarding the Almudaina Palace; the cathedral, golden and massive, rises beyond. Where you exit the garage, there's a ceramic mural by the late Catalan artist and Mallorca resident Joan Miró, facing the cathedral across the pool that runs the length of the park.If you begin early enough, a walk along the ramparts at Ses Voltes from the mirador beside the cathedral is spectacular. The first rays of the sun turn the upper pinnacles of La Seu bright gold and then begin to work their way down the sandstone walls. From the Parc de la Mar, follow Avinguda Antoni Maura past the steps to the palace. Just below the Plaça de la Reina, where the Passeig d'es Born begins, turn left on Carrer de la Boteria into the Plaça de la Llotja (if the Llotja itself is open, don't miss a chance to visit—it's the Mediterranean's finest Gothic-style civic building). From there stroll through the Plaça Drassana to the Museu d'Es Baluard, at the end of Carrer Sant Pere. Retrace your steps to Avinguda Antoni Maura. Walk up the Passeig d'es Born to Plaça Joan Carles I, then right on Avenida de La Unió.

The infinite variety of street life, the nooks and crannies of the medieval Barri Gòtic, the ceramic tile and stained glass of Art Nouveau facades, the art and music, the throb of street life, the food (ah, the food!)—one way or another, Barcelona will find a way to get your full attention. The capital of Catalonia is a banquet for the senses, with its beguiling mix of ancient and modern architecture, tempting cafés and markets, and sun-drenched Mediterranean beaches. A stroll along La Rambla and through waterfront Barceloneta, as well as a tour of Gaudí's majestic Sagrada Famíliaand his other unique creations, are part of a visit to Spain's second-largest city. Modern art museums and chic shops call for attention, too. Barcelona's vibe stays lively well into the night, when you can linger over regional wine and cuisine at buzzing tapas bars.