Piraeus is the third largest municipality in Greece, located in the Attica region. It lies about 10 kilometers from downtown Athens, to which it is a seaport, and is connected with a variety of buses, trolleys, but also the subway, tram, suburban railway and the future lines of Attica Metro. The port of Piraeus is the largest in Europe and one of the largest in the world in terms of passenger traffic and is the ideal starting point to travel to Greek islands. The gates of the port are configured depending on the destination of passenger ships. For example, northwest and western gates leading to docks approaching ships bound for the islands of the northeastern Aegean and Crete, while the central, the Cyclades and the Dodecanese.