The Alcázar of Segovia, like many fortifications in Spain, started off as a Roman fort, but apart from the foundations, little of the original structure remains. A Muslim era fort, and a such and such which was itself largely replaced by the present structure, was built by the Berber Almoravid dynasty. The first reference to this castle was in 1120, around 32 years after the city of Segovia returned to Christian hands (during the time when King Alfonso VI reconquered lands to the south of the Duero river down to Toledo and beyond).