History of Cologne was considered a substitute for the German University of Strasbourg, which became part of France along with the rest of Alsace. Cologne prospered during the Weimar Republic and progress was made especially in governance, city planning and social affairs. Social housing projects were considered exemplary and were copied by other German cities. As Cologne competed to host the Olympics, a modern sports stadium was erected at Müngersdorf. Beginning of the 1920s civil aviation was permitted once more, and Cologne Butzweilerhof Airport soon became a hub for national and international air traffic, second in Germany only to Berlin Tempelhof Airport. At
Historical Archive of the City of Cologne near the Cologne town hall. The records were for the most part those of real estate transactions: these were recorded on sheets of parchment or in books, which subsequently became known as "Schreinsbücher" (shrine books). In Cologne, these books can be traced back to AD 1130. Similar books from the late 12th century are known from the cities of Metz and Andernach. In the 19th century, all records of the old Cologne shrine quarters were transferred to the municipal archives. A municipal archive has existed since at least the year 1322. In 1326 the city council decided to establish the