The limestone cliffs overlooking St-Maurice impress many visitors. The limestone rocks that compose it come from the sedimentation of marine organisms (corals,...). There are many varieties of trees (maple, ash, beech, dogwood or spruce). Among the many thermophilic plants that thrive in the crevices are several rare species such as "Ruta graveloens" and wallflower. The hot and dry conditions allow many species such as the wall lizard or the green lizard to survive. It also serves as a breeding site for several species of birds linked to the rocks (peregrine falcon, great raven, rock swallow and window swallow). In winter, it is not uncommon to see the "Tichodroma muraria", a small bird with burgundy-colored wings and a curved beak. Chamois are very occasionally observed in the cliff.