Lacey V. Murrow Memorial Bridge, Seattle, U.S.A., 2,020 meters, 1940. The bridge carries the eastbound lanes of Interstate 90 across Lake Washington from Seattle to Mercer Island, Wash. The world’s first floating bridge to be built using concrete pontoons. It was designed by engineer Home Hadley, and constructed by the Puget Sound Bridge and Dredging Co,. at a price tag of $9 million. While under-going construction in 1990, an 850m long section of the bridge sank when a storm filled one pontoon. The rebuilt bridge reopened in 1993, at a cost of $93 million.