President Franklin Delano Roosevelt dedicated the original Mark Twain Memorial Bridge on September 4, 1936, with more than 75,000 people in attendance, and Missouri U.S. Senator and future president Harry S. Truman was among the dignitaries present. Designed solely for automobiles, it replaced reliance on the Wabash Train Bridge to the north, which had previously carried trains, automobiles, horse-drawn vehicles, and pedestrians. A toll was charged during its first four years in service to cover construction costs. The bridge spanned 2,636 feet across the Mississippi River and contained 5.3 million pounds of fabricated structural steel and 645,000 pounds of reinforcing steel. In summer, swarming mayflies attracted to the bridge lights sometimes covered the pavement 2 inches thick, making it extremely slick and requiring snow plows for removal. The bridge was closed from July to September during the flood of 1993, when water covered the approach on the Illinois side. It closed to traffic on Saturday, September 16, 2000, following the dedication and opening of the new Mark Twain Memorial Bridge, and demolition began on January 8, 2001, with the blasting of the first span; seven months were required to remove the old bridge. The bridge was named in tribute to Samuel L. Clemens, known as Mark Twain, on the centennial of his birth in A.D. 1935, as a Federal Emergency Administration of Public Works project built by the City of Hannibal, Missouri, in cooperation with the Hannibal Chamber of Commerce and financed with assistance from the Missouri State Highway Commission, the Illinois State Department of Public Works and Buildings, and Pine County, Illinois.