in the 20th century. It merged with the N&W in 1959. The opening of the coalfields made N&W prosperous and Pocahontas bituminous coal world-famous. Transported by the N&W and neighboring Virginian Railway (VGN), local coal fueled half the world's navies. Today it stokes steel mills and power plants all over the globe. The Norfolk & Western was famous for manufacturing steam locomotives in-house. It was N&W's Roanoke Shops that made the company known industry-wide for its excellence in steam power. The Roanoke Shops, with its workforce of thousands, is where the famed classes A, J, and Y6 locomotives were designed, built, and maintained. New steam locomotives were built there until 1953, long after diesel-electric had emerged as the motive power of choice for most North American railroads. About 1960, N&W was the last major railroad in the United States to convert from steam to diesel power. When N&W converted to diesel power, 2,000 railroad workers were laid off. The presence of the railroad also made Roanoke attractive to manufacturers. American Viscose opened a large rayon plant in Southeast Roanoke in October 1917. This plant closed in 1958, leaving 5,000 workers unemployed. Geography According to the United States Census Bureau, the city has a total area of , of which is land and (0.8%) is water. Roanoke is located in the valley and ridge province of Virginia immediately west of the Blue Ridge Mountains and east of the Allegheny Mountains. Within the city limits is Mill Mountain, which stands detached from surrounding ranges. Its summit features the Roanoke Star, Mill Mountain Zoo, the Discovery Center interpretive building, and an overlook of the Roanoke Valley. The Appalachian Trail runs through the northern section of Roanoke County several miles north of the city, while the Blue Ridge Parkway runs just to the south of the city. Carvins Cove, the second-largest municipal park in America at , lies in northeast Roanoke County and southwest Botetourt County. Smith Mountain Lake is several miles southeast of the city. The Jefferson National Forest is nearby. Roanokers and visitors to the area enjoy hiking, mountain biking, cross-country running, canoeing, kayaking, fly fishing and other outdoor pursuits. The city is located in the North Fork of Roanoke winemaking region. The "North Fork of Roanoke" appellation is a designated American Viticultural Area, recognizing the unique grape growing conditions present in the area. Valhalla Vineyards is located just outside the city