The minaret of San Juan is a tower belonging to an old mosque from the Emirate-Caliphate period, located in the Plaza de San Juan. It is one of the four minarets in Spain declared an Asset of Cultural Interest, framed as a Historic-Artistic Monument belonging to the National Artistic Treasure by decree of 3 June 1931. It is also located in the historic centre of Córdoba, declared a World Heritage Site by Unesco.

The minaret was probably built in the mid-9th or early 10th century, at the end of the Emirate of Córdoba and the beginning of the Caliphate, and served as a call to prayer for the mosque to which it was attached. According to a plaque found and preserved in the Archaeological Museum of Córdoba, the mosque was built by Cadi Umar ben Hadabas during the reign of Amir Abderramán II. Its height must have been higher than it is today and it would have been crowned with a crenellated terrace, in the style of Islamic constructions.

After the conquest of the city by the Castilian troops of Ferdinand III in 1236, it was ceded to the knights of the Order of St John of Jerusalem, also known as San Juan de los Caballeros, who built a church over the mosque. This would explain the name of both the minaret and the attached church. It is now part of this ecclesiastical complex and since 1880 has been part of the school that the Esclavas del Sagrado Corazón de Jesús (Handmaids of the Sacred Heart of Jesus) have in the city of Córdoba, as it was ceded by Bishop Ceferino González.

Although it was already identified as a minaret by Teodomiro Ramírez de Arellano in his work Paseos por Córdoba (1873-75), it would not be investigated until 1927 following alterations to the church by the architect Félix Hernández, who classified it as caliphal and also modified the second body and built the gabled upper part. In 1997 a grille was put in place to prevent landslides, which was removed during the first phase of restoration between October and December 2018 during an exterior restoration to prevent deterioration and to illuminate the monument. In April 2020 the Ministry of Culture of the Andalusian Regional Government gave the green light to the second phase, in which the interior part will be consolidated and the roof built in the early 20th century will be removed. The work began on 18 November of that year with a budget of 68,000 euros and should be completed before 31 December.

Built in the Emirate and Caliphate style, it has a square floor plan measuring 3.70 m on each side and a height of 10.92 m. It has a single body of ashlars arranged in a rope-and-tenon pattern with twin horseshoe arches on marble columns with Visigothic shafts. This first body was topped by a row of blind caliphal arches, which are no longer visible except for the three small columns that are still visible. The tower had a second section that was dismantled and replaced by the four-sloped roof it has today.

Despite its deterioration, it is, after the Great Mosque, the best example of Caliphate art preserved in the city. It is also the only intact minaret in Qurtuba; the others, such as those of Santa Clara or San Lorenzo or the one in the Aljama Mosque itself, were so modified over time that it is difficult to ascribe them to Emirate or Caliphate art.