The Landslide Blog is written by Dave Petley, who is widely recognized as a world leader in the study and management of landslides.
El Peñón de Guatapé is a famous landmark and tourist destination in Guatapé, Antioquia in Colombia. Consisting of a large granite inselberg that towers 200 m above the surrounding terrain, the rock attracts many visitors. At the base of the inselberg are located fruit and market stalls. This is an image of the site:-
On 2 November 2023, a small collapse occurred on the flank of El Peñón de Guatapé, with debris striking the pavement area at the foot of the landmark. News reports indicate that 17 people were injured. It is fortunate that no-one was killed. The following news report includes a video of the debris striking the ground:-
The news report above includes footage of the aftermath of the accident.
Interestingly, and fortunately, the collapse does not appear to be the granitic rock that forms El Peñón de Guatapé, but instead was soil and some plant debris. This is likely to have reduced the severity of the incident.
The rock has now been closed by the authorities whilst the risk to visitors is assessed.
Whilst conditions at the site appear to have been dry on the day of the accident, reports indicate heavy rainfall in the preceding days.
El Colombiano has an article (in Spanish) that explores the origin of the landslide, which reports that geologists at the site have identified a large crack (or gully) in the surface of El Peñón de Guatapé, in which organic material had collected. They quote a geologist as saying:
“…that crack was filled with soil, a kind of wedge that was held by friction against the rock, and perhaps some fragments of rock, so it was stable, but its equilibrium conditions were not.”