Samosierra AKA Bonbon Rapid Info
Samosierra is the most infamous rapid on the main section of the Rio Marañón. The rapid is several kilometers long, with multiple class IV sections near the top. At low-mid water, there is slow water to recover in after the class IV sections. At high water, the rapid links together and is nearly 7 km long, with the upper class IV sections running directly into a long stretch of class II-III.
Samosierra was created by an enormous landslide. The boulders from the slide have not settled, and as such, the rapid is constantly shifting. The rapid can vary greatly from trip to trip. Scouting its length is challenging due to the terrain. In the video below, two rafts navigate a new channel in Samosierra in October 2023. The new channel turned what is normally a class III section of the rapid into a substantial class IV section.
Locally, the rapid is known as Bonbon. The rapid is upstream of the most populous communities on the main section of the Marañón.