Archaeoseismological evidence of the Medina Azahara destruction in the early 11th century (Córdoba, Spain)

The "Caliphal City of Medina Azahara" was built in 936-937CE or 940-941CE (depending on the source) by the first Caliph of al-Andalus Abd al-Rahman III, being recently inscribed (2018) on the UNESCO World Heritage List. Its abandonment and destruction have been traditionally related to the civil war (“fitna”) initiated between the years 1009-1010. Besides that, other causes may have probably helped in the rapid depopulation and plundering of the city in the second decade of the 11^th century, barely eight decades after its foundation. The archaeoseismological study carried out on the remains of the caliphal city provides the first insights on the possible intervention of an earthquake in the destruction and sudden abandonment of the city.  The identified and classified Earthquake Archaeological Effects (EAEs) are dropped key stones in arches, tilted walls, conjugated fractures in brick-made walls, conjugated fractures and folds in regular pavements and dipping broken corners in columns. Up to 160 EAEs structural measures have been taken, the results of which are consistent with a mean ground movement direction of N140˚-160˚E. This geological structural analysis of preserved EAEs clearly indicates oriented damage, which can be reasonably related to the seismic destruction of Medina Azahara at the beginning of the 11^th century, although other contributing causes cannot be ruled out.