Las Gredas de Bolnuevo Curiosity · Mazarrón, Bajo Guadalentín, Murcia Las Gredas de Bolnuevo is a set of eroded rock formations facing the beach of Bolnuevo, in Mazarrón, also known as the Ciudad Encantada because of its resemblance to the homonymous site in Cuenca. Erosion has shaped rock mushrooms several metres tall and a rocky wall with similar shapes. The site lies next to the Sierra de las Moreras, protected as a natural area. Photo: Wikipedia / Wikimedia Commons (CC BY-SA) What to see and do in Mazarrón