Developed over Lower Cambrian marble, this is a karst area giving rise to a semi-enclosed valley whose waters flow into the El Mazo River. Limestone pinnacles, cliffs and caves appear from the wet meadowland. Oak, laurel and strawberry tree woods grow on the rocky land.
The dense, abundant vegetation makes it barely visible from the outside. Its relief is due to the combined action of natural phenomena and, above all, to intensive mining activity to obtain gold during Roman times.