The badland of Cornet cuts the slope of the range of Montlleó beside the path at the bottom end of the valley of Guardiola stream in the municipality of Castellgalí, shortly before reaching the large Cornet farmhouse that also gives its name to the stream in this stretch. The badland is made of poorly consolidated, blue or grey mudstones from Bartonian stage (Mid Eocene), in the external slope of a meander that the stream washes out and pushes away. The badland of Cornet reaches about 200 meters in length including the area that continues along a tributary ravine, and about 35 meters high in its central area. The most complete view of the badland of Cornet is from the opposite slope of the valley, this is from the way to the Sarri-Llar7 quarry and to Can Mas, rather than from the Cornet path at its bottom.
The badland of Cornet is very similar to that of Marganell; both are very steep areas displaying a pattern of erosion on prompt to crumble mudstones, that streams -respectively Cornet or Guardiola and Marganell- which can cause large floods as the ones in 10.06.2000 have cut.
In the neighbour municipality of Sant Vicenç de Castellet there are two badland areas named Muntanyes Russes and Can Forns de Vallhonesta, both in the same type of bluish mudstones but not in so tilted slopes. Over time without disturbances, plant debris on furrows kick off a self-accelerating process of soil formation and vegetation growth, a process to heal these badland wounds on the ground. However, the very tilt badlands of Cornet and Marganell maintain their geological nature.
[photo Jordi Badia]