Castildetierra in the Bardenas Reales, Navarre, Spain

In the heart of the Bardenas Reales of Navarre, a unique semi-desert landscape in Spain, rises Castildetierra, the most iconic rock formation in the area. Its silhouette, reminiscent of a natural tower eroded by wind and water, is a symbol of this territory declared a Biosphere Reserve by UNESCO.
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