Carcassonne Cathedral was built in the 13th century as a parish church, dedicated to Saint Michael. Following war damage in the 14th century it was rebuilt as a fortified church. In 1803 St. Michael's was elevated to cathedral status, replacing the earlier cathedral dedicated to Saints Nazarius and Celsus, now the Basilica of St. Nazaire and St. Celse.
The cathedral plan is characterised by its relative simplicity. It forms a single nave with a 20 metre high vault, lined with several lateral chapels. The chior screen has retained its 14th century stained glass. The sober façade has a single decorative feature in the form of a large rosette 8 meters in diameter, and the adjoining bell tower is relatively massive.References:
The city walls of Avila were built in the 11th century to protect the citizens from the Moors. They have been well maintained throughout the centuries and are now a major tourist attraction as well as a UNESCO World Heritage Site. Visitors can walk around about half of the length of the walls.
The layout of the city is an even quadrilateral with a perimeter of 2,516 m. Its walls, which consist in part of stones already used in earlier constructions, have an average thickness of 3 m. Access to the city is afforded by nine gates of different periods; twin 20 m high towers, linked by a semi-circular arch, flank the oldest ones, Puerta de San Vicente and Puerta del Alcázar.