The Alcázar of Toledo / The Alcázar Fortress
Its construction dates from Roman times. During the reigns of Alfonso VI and Alfonso X 'the Wise' it was rebuilt and became the first example of a square fortress with towers on the corners. It was once again rebuilt under Emperor Charles V, on this occasion by the architect Alonso de Covarrubias. The façades are Renaissance in style, and it has towers and crenellated defences according to a preliminary design by Alonso de Covarrubias, subsequently completed by Juan de Herrera. After the last reconstruction it became the site of the Army offices and museum.
For further info:
http://www.spain.info/en/que-quieres/arte/monumentos/toledo/alcazar_de_toledo.html
La Puerta de Bisagra / The Bisagra Gate
Of Arab origin, it was rebuilt by Alonso de Covarrubias in Renaissance-style, back in the 16th century. It has two sides. The one that faces the city opens up with a semicircular arch, flanked by two square towers with roofs and decorated with the coat of arms of Charles I. The outer side has an arch that bears the city's coat of arms. This arch is flanked by two huge circular towers.
For further info:
http://www.spain.info/en/que-quieres/arte/monumentos/toledo/puerta_nueva_de_bisagra.html
The Artistic Process
The Outcome