Adoption of the Dawes Plan by the German Government. The Allies end the occupation of the Ruhr. 1923 – Representatives from the towns of Köln, Düsseldorf und Duisburg found the "Studiengesellschaft für die rheinisch-westfälische Schnellbahn". A Schnellbahn (suburban railway) direct from Köln to Dortmund is planned. The Reichsbahn (National railway system) hinder these plans and intend to extend the current lines and construct their own Schnellbahn system. 1923 – The Westfalenhalle is opened in Dortmund. It becomes a location for six-day racing and other large sporting events, as well as political meetings of the Weimar Republic. 1925 – On 27 April 1925 Dortmund Airport is opened for business. Dortmund became a stop on the route Copenhagen-Hamburg-Bremen-Dortmund-Frankfurt(M)-Stuttgart-Zürich operated by Deutsche Luft Hansa (this was a different airport than the present-day Dortmund Airport). 1926 – Despite having been completed in 1921, the Wedaustadion in Duisburg is officially opened. With a capacity of 40,000 it is the second-largest in Germany after the Grunewaldstadion in Berlin. By 1922 the German Athletics Championships are being staged there. In 1924, Germany lost a football match for the first time on German soil, against Italy in the Wedaustadion, losing 1:0. 1928 – Paul Reusch founds the Ruhrlade in January 1928. 1928 – A period of boundary reforms. As a result, the "double-towns" of Gelsenkirchen-Buer and Duisburg-Hamborn were formed. Two years beforehand, this new construction had a precedence in the likes of Castrop-Rauxel and Wanne-Eickel. 1928 – During the Ruhreisenstreit (Ruhr Iron Strike) more than 200,000 employees of the iron and steel industry were locked out and had to be helped by the state. 1929 – The Volkspark Grugapark is opened as Große Ruhrländische Gartenbau-Ausstellung (Great Ruhr Garden Exhibition). 1929 – The Oberhausen Gasometer is completed, the largest gas holder in Europe. 1929 – The start of the world economic crisis causes the export-orientiated production of the coal and steel industry to collapse. 1932 – The Great Depression reaches its high point. Unemployment in the Ruhr stands 31.2%. Production of iron had reduced by 60%, and it was a similar situation in the steel and coal industries 1932 – The industrialist Friedrich Flick manages to sell his interest in Gelsenkirchen Bergwerke to the German government for about three times its market value, an event sometimes known as the Gelsenberg affair. 1933 – National Socialist takeover – the Steinwache in Dortmund becomes a prison and torture chamber of the