The 'flying train', overhead railway, Wuppertal, Germany, 21 March 1951. 'When there is no space left on the ground - take to the air. This principle has been adopted sucesfully in New York, where skyscrapers make up for the lack of space, and in Wuppertal, Germany, where an overhead railway has been running efficiently for 50 years.' This overhead railway runs along a long narrow valley and serves the industrial centre.
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