The Alcázar de los Reyes Cristianos is a medieval palace-fortress located in Cordoba, Spain, next to the Guadalquivir River. The fortress was built in the 14th century and served as the primary residence of the Catholic Monarchs, King Ferdinand II of Aragon and Queen Isabella I of Castile, during the time when they were planning the final push to recapture Granada from the Moors.

The palace is designed in a Mudejar style, blending Islamic and Christian elements, with an impressive array of towers, patios, gardens and fountains. It was also the site of many historical events, including the interrogation of Christopher Columbus by the Catholic Monarchs and the establishment of the Inquisition in Spain.

The fortress has undergone extensive renovations over the centuries, with different parts added and reconstructed to suit the needs of different occupants. The towers are a prominent feature, with the Torre del Homenaje (Tower of Homage) being the tallest at 25 meters. The fortress also includes the famous gardens, with lush greenery and ornate fountains that are still maintained to this day.

The Alcázar de los Reyes Cristianos has been designated as a National Monument since 1931 and is one of the most visited tourist attractions in Cordoba. It is also listed as a UNESCO World Heritage Site as part of the Historic Center of Cordoba.