The lacustrine limestones occur in extensive layers of light-coloured hard rock into the geological formation Artés that is mostly made of reddish, easier to wash out shales and sandstones. If the terrain and the strata share the same slope and the top layer is a lacustrine limestone, the roof of this hard stratum may turn to be the natural pavement of a path.
This situation beautifully occurs in the area that goes up from Viladelleva towards the range of Portell del Llop, on the boundaries between Callús and Súria municipalities (photos 1st and 2nd) as well as near the abandoned village of El Putxot, in Castellnou de Bages (photos 3rd and 4th). Notice that despite the four paths go up, the lacustrine limestone stratums stay on the surface because they tilt southward as the ground slope, after being located on the southern flank of the Balsareny anticline or Mig-Món fault.
[photos Montserrat Porta and Jordi Badia]