of these arches were walled up during the Christian period (after 1236) as chapels were built along the northern edge of the hall. The courtyard of the original mosque of Abd ar-Rahman I had no surrounding gallery or portico, but it is believed that one was added by Abd ar-Rahman III between 951 and 958. The current gallery, however, was rebuilt with a similar design by architect Hernán Ruiz I under Bishop Martín Fernández de Angulo between 1510 and 1516. The current layout of the gardens and trees is the result of work carried out under Bishop Francisco Reinoso between 1597 and 1601. Today the courtyard is planted with rows of orange trees, cypresses, and palm trees. Bell tower and former minaret thumb|One of the coat-of-arms on the Puerta de Santa Catalina (gate on the east side of the courtyard today) which depicts the minaret tower (serving as a bell tower) before its reconstruction in 1593Abd al-Rahman III added the mosque's first minaret (tower used by the muezzin for the call to prayer) in the mid-10th century. The minaret has since disappeared after it was partly demolished and encased in the Renaissance bell tower that is visible today, which was designed by Hernán Ruiz III and built between 1593 and 1617. The minaret's original appearance, however, was reconstructed by modern Spanish scholar Félix Hernández Giménez with the help archeological evidence as well as historical texts and representations. (For example, the two coat-of-arms on the present-day cathedral's Puerta de Santa Catalina depict the tower as it appeared before its later reconstruction.) The original minaret was 47 meters high and had a square base measuring 8.5 meters per side. Like other Andalusi and North African minarets after it, it was composed of main shaft and a smaller secondary tower or "lantern" (also with a square base) which surmounted it. The lantern tower was in turn surmounted by a dome and topped by a finial in the shape of a metal rod with two golden spheres and one silver sphere (often referred to as "apples") decreasing in size towards the top. The main tower contained two staircases, which were built for the separate ascent and descent of the tower. About half-way up, the stairways were lit by sets of horseshoe-arch windows whose arches were decorated with voussoirs of alternating colours which were in turn surrounded by a rectangular alfiz frame (similar to the