From the late 1800's through most of the 20th century, the Portsmouth area was served by the N&W, the B&O, and the C&O. The C&O's Sciotoville Bridge opened in 1917 after being built in 1915-1916, and its double span of 1,550 feet was for many years the longest continuous truss bridge in the world, considered an engineering marvel, and it remains one of the strongest bridges ever built. Major industries in the Portsmouth area today include grey iron castings produced by OSCO Industries Inc., the uranium enrichment plant near Piketon, Ohio, and scenes from the former Mitchellace Inc., the world's largest manufacturer of shoelaces, with views showing both past and present industry. Medical practice in the Portsmouth area progressed from Dr. Thomas Waller, the first physician in Portsmouth, attending a patient in the home to a present-day operating room, while local hospitals over the years culminated in Southern Ohio Medical Center, which opened in 1968, continues to expand its services, and is the largest facility of its kind in the south-central Ohio area. In the twentieth century, the United States fought for freedom worldwide in five major wars that began during that century, and thousands of men and women from southern Ohio either enlisted or were drafted into the armed forces during this period.