How did a single impact cause Baltimore’s Key Bridge to collapse? Engineers explain how a vulnerability made the bridge - once considered an engineering marvel - open to catastrophe. Learn more on "Baltimore Bridge Collapse," available to stream now ➡️ https://to.pbs.org/41fRG3T | NOVA l PBS

What causes bridges to deteriorate? More than half of the bridges in the U.S. are in “fair” condition. We looked into the key factors contributing to bridge deterioration. See the interactive, 3D models here: http://www.kcci.com/article/3d-models-bridges/64188751 | KCCI