Reyes Cristianos Alcázar is a military building in the city of Córdoba, Spain, located on one of the banks of the Guadalquivir River.

The monarch Alfonso XI of Castile ordered its construction in 1328 on the old Andalusian Alcazar, formerly the residence of the Roman governor and customs. The architectural complex has a sober character on the outside and splendid on the inside, with the magnificent gardens and patios that maintain a Mudejar inspiration.

The Alcázar has been declared an Asset of Cultural Interest since 1931. It is part of the historic center of Córdoba, declared a World Heritage Site by Unesco in 1994. In 2019 it received 595,517 visitors, being the second most visited paid monument in Córdoba after the Mosque.

At night time, since 2011, the Magic Nights have been held at the Alcázar, a show of light, water and sound that explains the history of the monument through a striking staging.

The first references to this place date back to Roman times, when Córdoba was the capital of Hispania Ulterior and housed a river customs office in the same space. The oldest remains have been found in the Patio de las Mujeres, like a Roman wall from the 1st century after the re-founding carried out by Emperor Augustus. Likewise, remains from the V and VI centuries where remains of a castellum attached to said wall that had the function of protecting the Roman bridge and the river port were found. Julius Caesar arrived at this political and administrative center to perform the tasks of quaestor in 65 BC. and he would have planted various fruit and exotic species, such as the oriental banana, this event appearing in a contemporary poem by Marcial. This was probably because the banana brought good fortune on the battlefield.

During the Emirate of Córdoba, the so-called Andalusian Alcazar was built, which was a royal residence for several centuries. The gardens were built under the mandate of Abderramán II, since it was then that an aqueduct was built that carried water from the Guadalquivir to the fortress. The Alcázar lost relevance with the establishment of the Caliphate of Córdoba and the transfer of the court to Medina Azahara, although after the fall of the Caliphate it became a royal residence again. Similarly, there is evidence of the construction of an Almohad citadel later.

After the Castilian conquest of the city, the site occupied by the old Andalusian fortress was divided between King Fernando III, Bishop Lope de Fitero, some nobles and the Order of Calatrava. The sovereign Alfonso X the Wise began the first Christian constructions on the Muslim ones such as the Tower of the Lions and a wall canvas, although most of its construction occurred from 1328 at the hands of Alfonso XI of Castile, who projects a space quadrangular of 4,000 square meters and builds the Mudejar baths for his Sevillian lover Leonor de Guzmán.

The last monarchs to inhabit the Alcázar were the Catholic Monarchs, spending more than eight years in the fortress, from where they would lead the campaign against the Nasrid Kingdom of Granada and planned the conquest of the Canary Islands, eventually having Fernando's wife retained. Guanarteme.

In 1812, and after the abolition by the Constituent Courts of Cádiz of the Tribunal of the Inquisition, it became a civil prison until, in 1931, it was used for military installations.