Shortly after the Romans founded Cologne in 50 AD, they built a wall around the city. The wall was first expanded in the tenth century, and again in 1106, but due to the continuing growth of the city a new, 7 meters high wall was built in the twelfth and thirteenth centuries.
The most important of the twelve gates that gave entrance to Cologne was the west gate, known as the Hahnentor. After their coronation in Aachen, German kings arrived in Cologne through this gate to revere the shrine of the Three Magi in the Cologne cathedral. The gate was built between 1235 and 1240 and was probably named after a citizen named Hageno, who owned the nearby land.
The Hahnentorburg has two semi-circular, crenellated towers. The city's coat of arms is depicted above the entrance. The tower was restored in 1890 by the city architect Josef Stubben; a memorial plaque commemorates the architect's construction of Neustadt (new city) between 1881 and 1898 outside the former city walls. The tower was severely damaged during the Second World War, but was later reconstructed.
References:Saint-Georges de Boscherville Abbey is a former Benedictine abbey. It was founded in about 1113 by Guillaume de Tancarville on the site of an earlier establishment of secular canons and settled by monks from the Abbey of Saint-Evroul. The abbey church made of Caumont stone was erected from 1113 to 1140. The Norman builders aimed to have very well-lit naves and they did this by means of tall, large windows, initially made possible by a wooden ceiling, which prevented uplift, although this was replaced by a Gothic vault in the 13th century. The chapter room was built after the abbey church and dates from the last quarter of the 12th century.
The arrival of the Maurist monks in 1659, after the disasters of the Wars of Religion, helped to get the abbey back on a firmer spiritual, architectural and economic footing. They erected a large monastic building one wing of which fitted tightly around the chapter house (which was otherwise left as it was).