Machu Picchu was built in the 1400s and then later rediscovered in 1911. By 1976, 30% of Machu Picchu had been restored and restoration still continues. In 1981 it was made a protected area and called a Peruvian Historical Sanctuary. It became a World Heritage Site by UNESCO in 1983. The Management Unit of the Historic Sanctuary of Machu Picchu (UGM) was created in 1999 to help manage Machu Picchu as a protected area. The UGM was reactivated in 2011 and continues to manage today (UNESCO).