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Located between Viladecavalls and Olesa de Montserrat, in the Baix Llobreghat, we find some curious formations of crumbled rock forming a landscape of exceptional and protected geological interest, as we appreciate in these snapshots in Las Fotos de los Lectores de La Vanguardia.

These gigantic formations are a key source of information to understand the geology of Catalonia. You can see the fault that brings into contact the Paleozoic materials (from the primary era) and the Cenozoic materials (from the Tertiary era) and that separates the Catalan Pre-coastal Mountain Range from the Vallès-Penedès tectonic trench.

This fault is related to the circulation of thermal waters that have sprung up in several nearby places, such as La Puda de Montserrat, Caldes de Montbui or la Garriga.

As highlighted in the Cultural Heritage Maps of the Barcelona Provincial Council, we are facing “a place of exceptional geological interest, named for the bluish color of the area.”

This fault, which emerges in an exceptional way due to the erosive action carried out by the Sant Jaume stream, “provides invaluable data for the interpretation of the geological history of Catalonia and, at the same time, allows an observation of recent tectonics ( earthquakes, etc)”.

Its age is between 400 and 450 million years. The fault presents a gap with a width of almost 100 meters, and is formed by chopped and crushed Paleozoic materials with a floury appearance and texture.