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:The stone church of Gamla Uppsala, built over the pagan temple, dates from the early 12th century. Due to fire and renovations, the present church is only a remnant of the original cathedral.
Before the arrival of Christianity in Sweden, Gamla Uppsala was the seat of Swedish kings and a ceremonial site known all over northern Europe. The settlement was home to royal palaces, a royal burial ground, and a great pagan temple. The Uppsala temple, which was described in detail by Adam of Bremen in the 1070s, housed wooden statues of the Norse gods Odin, Thor and Freyr. A golden chain hung across its gables and the inside was richly decorated with gold. The temple had priests, who sacrificed to the gods according to the needs of the people.
The first Christian cathedral was probably built in the 11th century, but finished in the 12th century. The stone building may have been preceded by a wooden church and probably by the large pagan temple.