Athens is loaded with museums. It seems like there are new museums and branches of old museums opening every week.
You can check the Athens News for traveling exhibits and this page will give you information on the main museums that should not be missed.
An excellent book to get is The Museums of Athens by Aristidis Michalopoulos which is the most complete guide to Athens Museums that I have found. It contains opening and closing hours, entrance fees, and maps and descriptions on how to get to museums in Athens and Pireaus, the suburbs and nearby islands.
National Archaeological Museum
The National Archaeological Museum ranks among the top ten museums in the world. Its impressive collection is housed in a beautiful neoclassic building near the juncture of Alexandras Avenue on Patission Avenue. There is a gift shop, and a cafe in the sculpture garden. Children under 6 and EU students get in free.
The museum is a five minute walk from Victoria Station and a 10 minute walk from Omonia. The Trolly #’s 1,2,3,5,6,7,8,9,11,13, and 15 all stop there. W ell not exactly at the museum. They actually stop by Tositsa Street and you have to walk past a bunch of drug addicts to get there but they probably won’t bother you. They have their own problems. If the only day you can come is Sunday don’t bother. Only 8 of the 64 galleries are open due to a shortage of funds, and you still have to pay the same price.
The Acropolis Museum
The new Acropolis Museum was designed to offer the best conditions for the exhibition of its exhibits. A walk through its galleries is a walk through history between the masterpieces of the Archaic and Classical periods, but also in the ancient neighborhoods of Athens whose city streets and buildings you can see below when you look through the glass floors of the museum. It was hoped that by building the Acropolis Museum, the British Museum would return the Elgin Marbles, but don’t hold your breath. In the meantime there are copies of those pieces to go along with the thousands of ancient stones and statues that finally have a home, worthy of them. Don’t miss this museum.