The Tacoma Narrows Bridge was open for about four months in 1940 before a steady wind set it twisting and ultimately tore the bridge apart.
Damn Interesting has a detailed account of the bridge’s short history and demise.
After opening, the new bridge shortly came to be known as “Galloping Gertie,” so named by white-knuckled motorists who braved the writhing bridge on windy days. Even in a light breeze, Gertie’s undulations were known to produce waves up to ten feet tall. Sometimes these occurrences were brief, and other times they lasted for hours at a time. Numerous travelers shunned the route altogether to avoid becoming seasick, whereas many thrill-seeking souls paid the 75-cent toll to traverse Gertie during her more spirited episodes.
The 99% Invisible podcast devoted a show to the collapse of the bridge.
(via sarah pavis)