The Acropolis Museum was built to host all of the archaelogical findings of the Acropolis site. It opened to the public in 2009. The building's architecture was designed to be in constant dialogue with the Acropolis itself — its glass walls allow the view of the Acropolis walls and the Parthenon, and the transparent floors let the eye wander over the archaelogical excavation that sits beneath the museum. As the sky goes dark at night, the Parthenon lits up, and you can get a great view of the scenery.
Because September 27th was World Tourism Day, access to the museum was free from 5pm to 10pm, and there were also free tours of the permanent collection, with museum archaelogists. We highly recommend this tour! Other highlights of the museum are the "reading panel", a room where you can sit comfortably overlooking the Caryatids and read books about Ancient Greek Art, and the many models of the Acropolis buildings — there is even one made entirely out of Legos!
Unfortunately, in most areas of the museum photographs were not allowed — one more reason for you to put this place in your bucket list!