From this point we can see a large outcrop of granite which, because of the high level of erosion, clearly displays large joints or fractures. This fracturing can result from the combination of two factors: (1) the pressure relief that rocks will experience when the load of overlying rocks is removed as they get nearer to the earth’s surface causing fractures; (2) the action of agents of erosion (water, ice and biological agents). Rainwater plays a significant role in this process through infiltrating the fissures that open up due to this pressure relief and then circulating in the centre of the granite masses, acting on the minerals in the granite thereby causing their breakdown. Ice can also promote the fracturing of granite. The continual cycle of freeze-thaw, resulting from the rise and fall of temperature, releases a group of physico-chemical processes that affect the granite. The transformation of liquid water to ice can act like a wedge (as a result of the increase in volume) and, consequently, develop internal pressures in the rock, opening up fissures and aiding fragmentation. On the other hand, biological agents (plants and animals) also exercise their own form of wearing down of the rocks. At this outcrop can be seen an example of the mechanical action of tree roots on rocks (through occupying cracks and then provoking the physical disintegration of the rock).