Decksteiner Weiher

This guide to the Decksteiner Weiher in Cologne opens with a puzzle: how do you fill a lake nearly the size of thirty football pitches when no river feeds it? It traces the lake's creation between 1927 and 1929 by city planner Theodor Nussbaum, an obsessive rower who shaped it as a dead-straight rowing course rather than a scenic pond, dug from the ruins of a torn-down fortress belt. You'll hear about the unemployment-relief crews who piled the excavated soil into the sledding hills nearby. Stand at the geometrically straight shoreline and see if you can guess where the water actually comes from.