Lisbon is the capital and the largest city of Portugal, with an estimated population of 505,526 within its administrative limits in an area of 100.05 km2. Its urban area extends beyond the city's administrative limits with a population of around 2.8 million people, being the 11th-most populous urban area in the European Union. About 3 million people live in the Lisbon Metropolitan Area (which represents approximately 27% of the country's population). It is mainland Europe's westernmost capital city and the only one along the Atlantic coast. Lisbon lies in the western Iberian Peninsula on the Atlantic Ocean and the River Tagus. The westernmost areas of its metro area form the westernmost point of Continental Europe, which is known as Cabo da Roca, located in the Sintra Mountains.

Alicante, or Alacant , both the Spanish and Valencian being official names, is a city and port in Spain on the Costa Blanca, the capital of the province of Alicante and of the comarca of Alacantí, in the south of the Valencian Community. It is also a historic Mediterranean port. The population of the city of Alicante proper was 330,525, estimated as of 2016, ranking as the second-largest Valencian city. Including nearby municipalities, the Alicante conurbation had 452,462 residents. The population of the metropolitan area (including Elche and satellite towns) was 757,085 as of 2014 estimates, ranking as the eighth-largest metropolitan area of Spain.

Olbia is a city and comune of 60,345 inhabitants (May 2018) in the Italian insular province of Sassari in northeastern Sardinia (Italy), in the Gallurasub-region. Called Olbia in the Roman age, Cività in the Middle Ages (Giudicati period) and Terranova Pausaniabefore the 1940s, Olbia was again the official name of the city during the period of Fascism.

Genoa is the capital of the Italian region of Liguria and the sixth-largest city in Italy. In 2015, 594,733 people lived within the city's administrative limits. As of the 2011 Italian census, the Province of Genoa, which in 2015 became the Metropolitan City of Genoa, counted 855,834 resident persons. Over 1.5 million people live in the wider metropolitan area stretching along the Italian Riviera.

 Located on the Gulf of Genoa in the Ligurian Sea, Genoa has historically been one of the most important ports on the Mediterranean: it is currently the busiest in Italy and in the Mediterranean Sea and twelfth-busiest in the European Union. Genoa has been nicknamed la Superba ("the proud one") due to its glorious past and impressive landmarks. Part of the old town of Genoa was inscribed on the World Heritage List (UNESCO) in 2006 as Genoa: Le Strade Nuove and the system of the Palazzi dei Rolli. The city's rich cultural history in art, music and cuisine allowed it to become the 2004 European Capital of Culture. It is the birthplace of Christopher Columbus, Andrea Doria, Niccolò Paganini, Giuseppe Mazzini, Renzo Piano and Grimaldo Canella, founder of the House of Grimaldi, among others.

Genoa, which forms the southern corner of the Milan-Turin-Genoa industrial triangle of Northwest Italy, is one of the country's major economic centers. The city has hosted massive shipyards and steelworks since the 19th century, and its solid financial sector dates back to the Middle Ages. The Bank of Saint George, founded in 1407, is among the oldest in the world and has played an important role in the city's prosperity since the middle of the 15th century. Today a number of leading Italian companies are based in the city, including Fincantieri, Selex ES, Ansaldo Energia, Ansaldo STS, Edoardo Raffinerie Garrone, Piaggio Aerospace, Mediterranean Shipping Company and Costa Cruises.