Before you stands the thomas Viaduct, named after Philip E. Thomas, the first president of the Baltimore & Ohio Railroad. This unique bridge has become an enduring symbol of the B&O Railroad and the Patapsco Valley, surviving several floods and outlasting many modern structures.
In 1833, B&O engineers sough to build a first-class railroad line with gentle curves and low grades from Baltimore to Washington D.C. Spanning the cavernous Patapsco Valley was a formidable challenge. Benjamin latrobe, Jr. not only met this obstacle, but designed an engineering marvel.
Completed in July 1835, the Thomas Viaduct was among the largest stone-arched bridges in the world. The 704 foot curved bridge is 66 feet hight and connects Relay to Elkridge on eight eliptical arches. Though critics thought it incapable of bearing itw own weight, the viaduct not only carried the first steam locomotives, but also continues to support modern-day trains.
The Real Heroes
Hundreds of immigrant workers built the Thomas Viaduct under the hard-driven direction of John McCartney. Working for low wages and living in improvise shantytowns, the laborers used hand tools, wheelbarrows, primitive pulleys, along with sweat and muscles to hoist 63,000 tons of granit into place. Several workers were killed building the Thomas Viaduct.
Civil War Chokepoint
Prior to 1872, the B&O's Washington Branch was the federal capital's only direct rail and telegraph link with the North. During the Civil War, protecting this connection proved critical to the Union war effort. To discourage Confederate raiders and saboteurs, Union troops began a four-year occupation of Relay and Elkridge in 1861 to protect the railroad. Union General Benjamin F. Butler used the camp at Relay as a staging area for his occupation of Baltimore's Federal Hill, securing the city for the Union.