Views of cruise ships in Port of Barcelona from the Montjuic Castle old military fortress on Montjuic Mountain overlooking the city, Barcelona, Catalonia, Spain, Europe

A view of the industrial and militarized Russian seaport city of Murmansk on the northern shore of the Kola Peninsula, Murmansk Oblast, Russia, Arctic, Europe

A large red cargo ship in calm waters, close to the shoreline of a coastal city, Portugal

View of Kavala port from elevated position, Dimos Kavalas, Eastern Macedonia and Thrace, Gulf of Thasos, Gulf of Kavala, Thracian Sea, Greece, Europe

Falklands Island fisheries patrol ship the outer harbor of Stanley on East Island, Falkland Islands

Commercial ferries taking people and vehicles from one side to the other in Sognefjord, Norway

A view of the industrial and militarized Russian seaport city of Murmansk on the northern shore of the Kola Peninsula, Murmansk Oblast, Russia, Arctic, Europe

British International helicopter flying over the outer harbor of Stanley on East Island, Falkland Islands

A view of the industrial and militarized Russian seaport city of Murmansk on the northern shore of the Kola Peninsula, Murmansk Oblast, Russia, Arctic, Europe

View of the busy port city of Dakar, Senegal, West Africa, Africa

View of the busy port city of Dakar, Senegal, West Africa, Africa

View of the busy port city of Dakar, Senegal, West Africa, Africa

Views of Base Presidente Eduardo Frei Montalva, Antarctica, Southern Ocean, Polar Regions