The next master of whom there is information was Alvar Martínez (in some sources called González), who was quantity surveyor of the Olihuelas limestone quarries at the boundary of Olías del Rey. He is the designer of the west façade whose construction was begun in 1418. Changes made in 1787 obscure the original appearance of this façade. He was also the designer of the only tower of the cathedral, which was built during the office of Archbishop Juan Martínez de Contreras, whose coat of arms appears in the frieze that crowns the first section. The crowning of the tower was done by another great master sculptor, the Fleming Hanequin de Bruselas, who moulded the coat of arms of the succeeding archbishop Juan de Cerezuela. With Hanequin came a group of illustrious masters: Egas Cueman (de Bruselas' brother) , Enrique Egas, and Juan Guas; these worked on façades, chapels, and sumptuary works, completing the work done in the Gothic idiom with their labor. The vaults at the footing of the central nave were closed in 1493, under the direction of Juan Guas and Enrique Egas, with the patronage and supervision of Cardinal Mendoza.
