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.

Whilst the busy resort town of Kusadasi offers much in the way of shopping and dining – not to mention a flourishing beach life scene, the real jewel here is Ephesus and the stunning ruined city that really take centre stage. With only 20% of the classical ruins having been excavated, this archaeological wonder has already gained the status as Europe’s most complete classical metropolis. And a metropolis it really is; built in the 10th century BC this UNESCO World Heritage site is nothing short of spectacular. Although regrettably very little remains of the Temple of Artemis (one of the seven wonders of the ancient world), the superb Library of Celsus’ façade is practically intact and it is one of life’s great joys to attend an evening performance in the illuminated ruins once all the tourists have left. The history of the city is fascinating and multi-layered and it is well worth reading up on this beforehand if a visit is planned. Another point of interest for historians would be the house of the Virgin Mary, located on the romantically named Mount Nightingale and just nine kilometres away from Ephesus proper. Legend has it that Mary (along with St. John) spent her final years here, secluded from the rest of the population, spreading Christianity. An edifying experience, even for non-believers. For the less historical minded amongst you, Kusadasi offers plenty in the way of activities. After a stroll through the town, jump in a taxi to Ladies’ Beach (men are allowed), sample a Turkish kebap on one of the many beachfront restaurants and enjoy the clement weather. If you do want to venture further afield, then the crystal clear beaches of Guzelcamli (or the Millipark), the cave of Zeus and the white scalloped natural pools at Pamukkale, known as Cleopatra’s pools, are definitely worth a visit.

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.

Malta's capital, the minicity of Valletta, has ornate palaces and museums protected by massive fortifications of honey-color limestone. Houses along the narrow streets have overhanging wooden balconies for people-watching from indoors. Generations ago they gave housebound women a window on the world of the street. The main entrance to town is through the City Gate (where all bus routes end), which leads onto Triq Repubblika (Republic Street), the spine of the grid-pattern city and the main shopping street. Triq Mercante (Merchant Street) parallels Repubblika to the east and is also good for strolling. From these two streets, cross streets descend toward the water; some are stepped. Valletta's compactness makes it ideal to explore on foot. City Gate and the upper part of Valletta are experiencing vast redevelopment that includes a new Parliament Building and open-air performance venue. The complex, completed mid-2013, has numerous pedestrian detours in place along with building noise and dust. Before setting out along Republic Street, stop at the tourist information office on Merchant Street for maps and brochures.

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.