Castillo de Zafra Frongia

Spain, Spain

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The Castillo de Zafra Frongia, more commonly known as the Castillo de Zafra, is a striking 12th-13th century fortress dramatically perched on a sandstone outcrop in the Sierra de Caldereros near Campillo de Dueñas, Guadalajara province, Castilla-La Mancha, Spain.

Originating from an Arab stronghold overtaken by Christians in 1129 during the Reconquista and mentioned in the 1154 Fuero de Molina, it features thick defensive walls crowning a flat rocky summit, multiple towers including a prominent keep, and ingenious access via a narrow, zigzag path that made it nearly impregnable, capable of housing over 500 defenders with possible subterranean caves.

Passed among nobles like the Lara family, it withstood sieges including one by Ferdinand III in 1222, before falling into ruin by the 16th century, now preserved as a dramatic ruin evoking Tolkien-esque fantasy amid remote mountain scenery.