Piraeus is a port city in the region of Attica, Greece. Piraeus is located within the Athens urban area, 12 kilometres southwest from its city center, and lies along the east coast of the Saronic Gulf.
According to the 2011 census, Piraeus had a population of 163,688 people within its administrative limits, making it the fourth largest municipality in Greece and the second largest within the urban area of the Greek capital, following the municipality of Athens. The municipality of Piraeus and several other suburban municipalities within the regional unit of Piraeus form the greater Piraeus area, with a total population of 448,997.
Piraeus has a long recorded history, dating to ancient Greece. The city was largely developed in the early 5th century BC, when it was selected to serve as the port city of classical Athens and was transformed into a prototype harbour, concentrating all the import and transit trade of Athens. During the Golden Age of Athens the Long Walls were constructed to connect Athens with Piraeus.