Piraeus has its own museums, and its better to be in their own list.
Archaeological Museum of Piraeus, Ch. Trikoupi 31, +302102104521598
Hellenic Maritime Museum, Akti Themistokleous Mariza Zeas, Piraeus, +302104286959, http://hmmuseum.gr/
Municipal Art Gallery of Piraeus, Iroon Politehniou 91, Piraeus
Panos Aravantinos Decor Museum, building of Municipal theater of Piraeus, Iroon Politehniou 32, Piraeus