Machu Picchu on 1 April 2010. In July 2011, the Dirección Regional de Cultura Cusco (DRC) introduced new entrance rules to the citadel of Machu Picchu. The tougher entrance rules attempted to reduce the effect of tourism. The entrance was limited to 2,500 visitors per day, and the entrance to Huayna Picchu (within the citadel) was further restricted to 400 visitors per day. In May 2012, a team of UNESCO conservation experts called upon Peruvian authorities to take "emergency measures" to further stabilize the site's buffer zone and protect it from damage, particularly in the nearby town of Aguas Calientes, which had
Machu Picchu an Inca grass rope bridge, across the Urubamba River in the Pongo de Mainique, provided a secret entrance for the Inca army. Another Inca bridge was built to the west of Machu Picchu, the tree-trunk bridge, at a location where a gap occurs in the cliff that measures . The city sits in a saddle between the two mountains Machu Picchu and Huayna Picchu, with a commanding view down two valleys and a nearly impassable mountain at its back. It has a water supply from springs that cannot be blocked easily. The hillsides leading to it were terraced, to provide