1 Answer

There are several articles of concern dated 2008, including the threat of kidnapping. But I think you are more interested in something along the lines of:

The area is subject to natural hazards such as landslides, earthquakes and floods, with a direct effect on the conservation of the archaeological sites, on the accommodation facilities, on road and railway infrastructures, and on the safety of workers, inhabitants and tourists as well. The hazard for the archaeological remains as well as for site residents and visitors was recognized by UNESCO that, in 2008, threatened to expel Machu Picchu from the list of the World Heritage Sites.

In addition, past studies (Sassa et al., 2002) hypothesized the presence of a deep-seated planar low angle rock slide, which would lead to a collapse of the ridge on which the citadel of Machu Picchu rises. This hypothesis raised great clamour from the scientific and political points of view, impacting the tourist flow. On these assumptions, a scientific analysis of the risks which the Machu Picchu historical sanctuary, the Machu Picchu citadel and Aguas Calientes are subject to was carried out under the Interfrasi (2001-2005) and Forgeo (2008-2009) ENEA projects.