El gorg de la Llosa (= the pool of the Paving Stone) is located in the stream of Guardiola where it makes the boundary between the municipalities of Sant Salvador de Guardiola to the south and Manresa to the north, before the pool of L’Oller. The itinerary M-3 of the Green Belt of Manresa drives to visit it. The pool of the Paving Stone used to be one place to take one bath in summer time in the 60’s and 70’s of the former century.
One more than one meter thick, compact and cemented layer of rock made of mostly small particles of calcium carbonate nature outcrops on the right riverside, in the municipality of Guardiola. This rock layer tilts towards the northwest in perpendicular to the water flow. The stream flows above the sandstone and discovers its surface. The stream enlarges the surface of naked rock –the Paving Stone that names the pool- before being able to crop it, jump over and make the pool below. One set of parallel to the slope cracks at regular distances draws a beautiful geometry.
The display of the rock in vertical cliffs is common in the district of Bages, though not wide top surfaces of a naked rock stratum.
The rock layer of El gorg de la Llosa has marine origin, though it is close to the transition to the reddish rocks from continental origin that outcrops nearby to the west and in upper stratigraphic position.