The rocks break, the rivers drag them and round them off, and finally the pebbles sediment. Over the years they cement together and form conglomerates, other rocks... And the story starts all over again: The break off, they fall, they sediment and then become compacted once more...
Descending from Montcortès to La Pobleta, we can see these standing stones. In the process of erosion of the red conglomerates, the large blocks better resist erosion by the rain and wind, for many years protecting the materials underneath, forming this kind of chimney group.
A block of conglomerate with rounded edges, a "pebble of pebbles". The pebbles forming this conglomerate were formed some 500 mya, the conglomerate was formed some 250 mya, and the last deposit, which we can see being eroded now, must have been formed some 30 mya.