Machu Picchu risks of landslides, earthquakes and injury due to decaying structures. Nude tourism is a recent trend, to the dismay of Peruvian officials. In several incidents, tourists were detained for posing for nude pictures or streaking across the site. Peru's Ministry of Culture denounced these acts for threatening Peru's cultural heritage. Cusco's Regional Director of Culture increased surveillance to end the practice. In January 2010, heavy rain caused flooding that buried or washed away roads and railways to Machu Picchu, trapping more than 2,000 locals and more than 2,000 tourists, later airlifted out to safety. Machu Picchu was temporarily closed, reopening
Lost city few or no clues to their decline. For example, Malden Island, in the central Pacific, was deserted when first visited by Europeans in 1825, but the unsuspected presence of ruined temples and the remains of other structures found on the island indicate that a population of Polynesians had lived there for perhaps several generations some centuries earlier. Prolonged drought seems the most likely explanation for their demise and the remote nature of the island meant few visitors. With the development of archaeology and the application of modern techniques, many previously lost cities have been rediscovered. Machu Picchu is a pre-Columbian