The Rieskrater Museum, sometimes known in English as the Ries Crater Museum, focuses on meteors and their collisions with Earth. The museum is housed in a 16th-century barn in Nordlingen, Germany which was part of the medieval city's center. The area is the location of a meteor's impact with Earth c. 15 million years ago and it might have been a double impact (Steinheim crater is nearby). It has been recognized as such since the early 1960s. The museum's collection includes a genuine moon rock from Apollo 16 on loan from NASA in return for using the Nordlingen crater for training for the Apollo 14 astronauts due to its similarities to a moon crater. The museum is affiliated with the nearby Geopark Ries (UNESCO - International Network of Geoparks), whose mission is to protect the crater. The museum opened in May 1990 and received its millionth visitor on 15 December 2012. File:NeuschwansteinMeteorite1-1.jpg|Meteoritenfragment Neuschwanstein I - 1705 Gram File:NoerdlingerRies topo.jpg|Nördlinger Ries, Steinheim crater, Danube, Stuttgart, Nuremberg and Munich File:RiesSteinheimMarkings.JPG|Nördlinger Ries and Steinheimer crater