Thomas Neill bridge construction photograph and ephemera collection, 1939-1940

Construction of the Tacoma Narrows Bridge began in Nov., 1938. The bridge opened on July 1, 1940, to public acclaim. Lauded as an essential economic and military portal to the Olympic Peninsula, its completion was called a triumph of man's ingenuity and perseverance. It had been completed in record time and, with a 2,800 ft. central span, was the third largest span in the world. Immediately upon its opening it began swaying in the wind, which earned it the nickname “Galloping Gertie.” Four months after it opened to the public the bridge fell, in what was later called "the Pearl Harbor of engineering."

Construction on the Lake Washington Floating Bridge began Dec. 29, 1939, and was completed on July 2, 1940. At the time of construction, the Lake Washington Floating Bridge was the largest floating structure ever built by man and the first reinforced concrete floating roadway bridge ever built.

Prior to construction of the Lake Washington Floating Bridge, the only routes from the east side of the lake to Seattle were around Lake Washington to the north or south. The floating design was chosen for two reasons. First, Lake Washington has an unstable floor and it was doubtful that any foundation for concrete piers could be found within a reasonable depth. Second, at the time of construction, the cost for an orthodox type of bridge from the west shore of Lake Washington to Mercer Island would have been approximately $18,000,000—almost five times the cost of a floating bridge covering the same distance.