The Puerta del Sol was built in the Mudejar style in the 14th century, with a rectangular plan ending in a semicircle, with a large pointed arch on columns, and slightly advanced compared to the horseshoe door. On the main arch there is a relief with a representation of the imposition of the chasuble on San Ildefonso, topped with a moon and a sun, which gives the door its name.

Two crenellated and windowed towers flank it, one semicircular and the other square.