This building was the royal residence of the Christian monarchs and subsequently the site of the Courts of the Holy Offices, a civil prison, and finally a military prison. It is set among magnificent gardens, including the garden known as the Avenue of the Monarchs which features statues of all the monarchs who had connections with the palace-fortress. It was declared a Historical Monument in 1931. The building is also part of the area declared a World Heritage site by UNESCO in 1994. Since 1986, its gardens have been protected by town planning laws. It stands on top of the remains of the former caliph's palace.
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