The Acropolis Museum (Greek: Μουσείο Ακρόπολης, Mouseio Akropolis) is an archaeological museum focused on the findings of the archaeological site of the Acropolis of Athens. The museum was built to house every artifact found on the rock and on the surrounding slopes, from the Greek Bronze Age to Roman and Byzantine Greece. It also lies over the ruins of Roman and early Byzantine Athens. The museum was founded in 2003, while the Organization of the Museum was established in 2008. It opened to the public on 20 June 2009. More than 4,250 objects are exhibited over an area of 14,000 square metres.
The first museum was on the Acropolis and was completed in 1874 and underwent a moderate expansion in the 1950s. However, successive excavations on the Acropolis uncovered many new artifacts which significantly exceeded its original capacity. An additional motivation for the construction of a new museum was that in the past, when Greece made requests for the return of the Parthenon Marbles from the United Kingdom, which acquired the items in a controversial manner, it was suggested by some British officials that Greece had no suitable location where they could be displayed. Creation of a gallery for the display of the Parthenon Marbles has been key to all recent proposals for the design of a new museum.