One of the key Russian museums, the Pushkin National Museum of Fine Arts was the idea of art historian Ivan Tsvetayev, who would subsequently manage it. The museum opened on May 31, 1912, and was then named Emperor Alexander III Museum of Fine Arts. It was initially an assemblage of ancient and medieval copies and replicas, created for educational purposes and put on public display. But the collection grew and became more diversified over time. Among the additions were rare impressionist works, paintings by Sandro Botticelli, Lucas Cranach, Nicolas Poussin, and the ancient Greek artifacts unearthed by Heinrich Schliemann in the ruins of ancient Troy. The museum currently holds over half a million exhibits in its three buildings, on display and in the storerooms. The main building is dedicated to those very ancient molds and medieval copies, from which the museum began, along with icons, frescoes and artworks in different genres, but no older than the 19th century. The "Museum of Private Collections" has no exhibits of its own, being fully reserved for exhibitions of artworks from Russian and foreign private collections, organized by the museum's curators, which remain on display very long here. The Art Gallery is devoted to 19th and 20th-century European and American art and, accordingly, exhibits European and American art from the past three centuries. The famous impressionist collection is also here. Each of the buildings has one must-see exhibition or another on display all the time, for which queues start forming early in the morning. The museum has a lecture hall, for which one-time tickets are available in advance. Music concerts are given at the Pushkin Museum during holidays and festivals.