Very fresh and modern filled with old stuff. Both replicas and old relics. But you must be interested to get out the most of your visit, otherwise you just walk around looking at statues. It says now pictures allowed but it's not completely true. Some areas they tell you to put camera away.
A tip for you who don't want to pay entrance you can visit the cafeteria on top with access to a viewing deck over Parthenon for free.

Visited this beautiful museum as part of personal tour of the Acropolis. After the Acropolis views, we visited this collection of amazing collection of historical pieces which puts into perspective and understanding of the contribution made by the Greeks to modern civilization. A really wonderful collection very well laid out to enable unrestricted viewing. A must see visit if you are in Athens but allow yourself 2 to 3 hours to enjoy this amazing museum.