In 1666, under the supervision of José de Vega y Verdugo, José de la Pea de Toro began building the Baroque-style façade of the cathedral that faces the Plaza de la Quintana; he was followed by Domingo de Andrade, who, in 1700, completed it with large columns that span two floors of windows, a balustrade with large pinnacles, and an aedicule with a vanished equestrian sculpture of Santiago. The lintel of this door features the royal coat of arms of Spain, which is how the Spanish monarchy originally entered the cathedral, hence the name.

The closest door to the steps is the so-called Puerta Santa or Puerta del Perdón (Holy Door or Door of Forgiveness), which is usually locked behind a grille and is only unlocked on December 31 of Jubilee years. It was a smaller gate, one of seven, and was named after Saint Pelayo, whose monastery stood just across the street. Saint James, with Athanasius and Theodore as his followers, is depicted in a niche over this door. The lower half and both sides of the entryway now have twenty-four images of prophets and apostles (including Saint James himself) from the original stone choir of Master Mateo. The actual Holy Door, leading to the apse's ambulatory, is located inside this doorway, reached via a tiny courtyard.