Cologne - Alteburger Wall

Cologne is the fourth-largest city in Germany - and one of the oldest. A Germanic tribe, the Ubii, had a settlement here, this was named by the Romans "Oppidum Ubiorum". In 50 AD, the Romans founded "Colonia Claudia Ara Agrippinensium", the city then became the provincial capital of "Germania Inferior".

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During WWII Cologne was bombed in 262 separate air raids. The first ever 1,000 bomber raid by the RAF (codenamed "Operation Millenium") was conducted on Cologne in May 1942. In April 1945, when the American armee reached Cologne, the city was completely ruined. About 90% of all houses in the inner city were - gone. In 1939 Cologne had had a population of more than 700.00. In spring 1945 there were only about 40.000, living in the ruins.

This video shows parts of the destroyed city
www.youtube.com/watch?v=l_pQdzhdD50

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That means, that there are not that many "complete" houses in Cologne older than 70 years. Here parts of the old facade were saved and got "integrated" into the new building.