St. Gangolf is the oldest of Bamberg's churches and comprises several styles. The parish church, a former convent of canons, was built in the 12th century under bishop Otto the Holy in a romanesque style and converted into a gothic style around 1400. It later received baroque furnishings and today boasts a romanesque nave, a gothic choir, rococo altars and a modern altar, thus spanning many centuries.
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.