99% Invisible

In 1943, the Army Corps of Engineers began construction on a scale model that could test flooding in all 1.25 million square miles of the Mississippi River. It would be a three-dimensional map of nearly half of the continental United … Continue reading → Subscribe to SiriusXM Podcasts+ to listen to new episodes of 99% Invisible ad-free and a whole week early. Start a free trial now on Apple Podcasts or by visiting siriusxm.com/podcastsplus.  Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.