Piraeus, is a port city within the Athens urban area, in the Attica region of Greece. It is located in the Athens Riviera, 8 kilometres southwest of Athens’ city centre, along the east coast of the Saronic Gulf.

Valletta (or Il-Belt) is the tiny capital of the Mediterranean island nation of Malta. The walled city was established in the 1500s on a peninsula by the Knights of St. John, a Roman Catholic order. It’s known for museums, palaces and grand churches. Baroque landmarks include St. John’s Co-Cathedral, whose opulent interior is home to the Caravaggio masterpiece "The Beheading of Saint John."

Syracuse is a city on the Ionian coast of Sicily, Italy. It's known for its ancient ruins. The central Archaeological Park Neapolis comprises the Roman Amphitheater, the Teatro Greco and the Orecchio di Dionisio, a limestone cave shaped like a human ear. The Museo Archeologico Regionale Paolo Orsi exhibits terracotta artifacts, Roman portraits and Old Testament scenes carved into white marble.

Civitavecchia is a coastal town northwest of Rome, in Italy. Built in the 2nd century, the Port of Civitavecchia still retains some of its original features, like the Roman Dock. The port area also includes the 16th-century Michelangelo Fort. Nearby, the National Archaeological Museum displays bronze and ceramic artifacts. Northeast of town are the Terme Taurine, the ruins of a Roman thermal bath complex.

Livorno is an Italian port city on the west coast of Tuscany. It's known for its seafood, Renaissance-era fortifications and modern harbor with a cruise ship port. Its central Terrazza Mascagni, a waterside promenade with checkerboard paving, is the city's main gathering place. The bastions of the 16th-century Fortezza Vecchia face the harbor and open onto Livorno's canal-laced Venezia Nuova quarter.

Nice, capital of the Alpes-Maritimes department on the French Riviera, sits on the pebbly shores of the Baie des Anges. Founded by the Greeks and later a retreat for 19th-century European elite, the city has also long attracted artists. Former resident Henri Matisse is honored with a career-spanning collection of paintings at Musée Matisse. Musée Marc Chagall features some of its namesake's major religious works.

Marseille, a port city in southern France, has been a crossroads of immigration and trade since its founding by the Greeks circa 600 B.C. At its heart is the Vieux-Port (Old Port), where fishmongers sell their catch along the boat-lined quay. Basilique Notre-Dame-de-la-Garde is a Romanesque-Byzantine church. Modern landmarks include Le Corbusier’s influential Cité Radieuse complex and Zaha Hadid’s CMA CGM Tower.

Palma is a resort city and capital of the Spanish island of Mallorca (Majorca), in the western Mediterranean. The massive Santa María cathedral, a Gothic landmark begun in the 13th century, overlooks the Bay of Palma. The adjacent Almudaina is a Moorish-style Arab fortress converted to a royal residence. West of the city, hilltop Bellver Castle is a medieval fortress with a distinctive circular shape.