The line 3 (Blue Line) runs from Nikaia station, through the central Monastiraki and Syntagma stations to Doukissis Plakentias avenue in the northeastern suburb of Halandri. It then ascends to ground level and continues to Eleftherios Venizelos International Airport, using the Suburban Railway infrastructure, extending its total length to . The spring 2007 extension from Monastiraki westwards to Egaleo connected some of the main night life hubs of the city, namely those of Gazi (Kerameikos station) with Psirri (Monastiraki station) and the City Centre (Syntagma station). Extensions are under construction to the west southwest suburbs of Athens, as far as the port of Piraeus. The new stations will be Maniatika, Piraeus and Dimotiko Theatro. The completed extension will be ready in 2022, connecting the biggest port of Greece, Piraeus Port, with the biggest airport of Greece the Athens International Airport.