December 21, 1829
The first stone arch railroad bridge in the United States was dedicated in Baltimore, Maryland. The Carrollton Viaduct, spanning over Gwynn’s Falls stream in the southwestern part of the city, was constructed by the Baltimore and Ohio Railroad.
James Lloyd designed this bridge, and Caspar Weaver oversaw its construction. During the nine months it took to build the structure, approximately 1,500 tons (1,360.8 metric tons) of granite were placed on top of wooden frameworks set up there. Once the keystones were put in place, the 80-foot (24.4-meter)-long section of the viaduct actually above the water became self-supporting.
The Carrollton Viaduct measures 312 feet (95 meters) in length and 65 feet (20 meters) in height. This bridge helped open a new chapter in American railroad history and played a pivotal role in making Baltimore a major force in the nation’s transportation network. The Carrollton Viaduct, which is now owned by CSX Transportation, also has the distinction of being the oldest railroad bridge in continuous use. It was named after Charles Carroll, a wealthy local landowner who is best known today as a signer of the Declaration of Independence.
The Carrollton Viaduct was designated a National Historic Landmark in 1971. (The above photo of the bridge was taken that same year.) In 1982, the American Society of Engineers designated this structure a National Historic Civil Engineering Landmark.
Photo Credit: Public Domain
For more information on the Carrollton Viaduct, please check out https://structurae.net/en/structures/carrollton-viaduct and https://www.loc.gov/item/md0908/