Central Library of the National Autonomous University of Mexico (UNAM) is the main library in the Ciudad Universitaria Campus. It holds one of the largest collections in Mexico. The building is covered with the mural "Historical Representation of Culture", created by Mexican artist Juan O'Gorman. His unique masterpiece has become one of the most iconic buildings in Mexico. The facades are covered with natural colored stones that shaped the mural which, when viewed from a distance, produce various hues. In 2007, UNESCO proclaimed the Central Library along with the Central Campus as World Heritage.