Piraeus is the biggest port in Greece. It serves many ferries to the Greek islands and to Italy. It is a very modern area with a lot of shops and cafes to relax. There are kiosks where you can buy your ferry ticket, travel agencies and canteens. Every Sunday there is flea market.
From Piraeus there are several spots where you can enjoy the view to the sea. On the other side of the peninsula, is the picturesque port of Zea, known as Zea Marina, where many private yachts moor and hydrofoils leave for the Saronic Gulf. North-east of Zea Marina one will encounter the little port Mikrolimano (small harbour), a beautiful area full of restaurants and bars. To reach Piraeus it is easy with the metro, and buses which go to the airport.