Near Thurmont in Frederick County, Maryland — The American Northeast (Mid-Atlantic)
Bowstring Arch Bridge
Photographed by Allen C. Browne, October 21, 2021
1. Bowstring Arch Bridge Marker
Originally spanning Big Pipe Creek in Detour, Carrol County, Maryland, this Bowstring Arch Bridge, circa 1872, was reduced in width and moved to its present site over Little Hunting Creek. Patented in the early 1840s by internationally known inventor Squire Whipple, the truss bridge was important to the industry and economics of young America. Borrowing their form from earlier wooden structures, the double iron was less susceptible to damage and wear from the elements. The prefabricated bridges were erected across rural America and many still span waterways.
Truss bridges depend on compression and tension for support against the forces of gravity. The arch itself is under compression and tends to be pushed together by forces acting on it. The thinner diagonal and vertical braces are subject to tension and help support the deck and arch of the bridge.
Erected by Catoctin Furnace Historical Society. (Marker Number 4.)
Topics. This historical marker is listed in these topic lists: Bridges & Viaducts • Industry & Commerce. A significant historical year for this entry is 1872.
Location. This marker has been replaced by another marker nearby. It was located near 39° 34.959′ N, 77° 26.069′
this page online
Regionally, this marker was in the Washington Metropolitan Area and in Central Maryland. It was also in the American Mid-Atlantic. Globally, it was in the North Atlantic Region, North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it found itself in what was once one of the original Thirteen Colonies and also the Antebellum South.
Other nearby markers. At least 8 other markers are within walking distance of this location: Powered by Water (a few steps from this marker); The Bridge that Moved (within shouting distance of this marker); Hidden Labor (within shouting distance of this marker); Ironmaster's Mansion (within shouting distance of this marker); From Mules to Motors (within shouting distance of this marker); Waste Management (about 400 feet away, measured in a direct line); A Lost Pond (about 400 feet away); Catoctin Furnace (about 500 feet away). Touch for a list and map of all markers in Thurmont.
Other markers no longer nearby. Raceway and Dam (was within shouting distance of this marker but has been replaced with another marker now near it); Ruins of the Ironmasters House (was within shouting distance of this marker but has been replaced with another marker now near it); Prosperity and Power (was within shouting distance of this marker but has been replaced with another marker now near it); Slag Heaps (was about 400 feet away but has been replaced with another marker now near it).
Photographed by Allen C. Browne, October 21, 2021
2. Bowstring Arch Bridge Marker
Photographed by Allen C. Browne, October 21, 2021
3. Bowstring Arch Bridge Marker
Photographed by Allen C. Browne, July 3, 2017
4. Bowstring Arch Bridge
Credits. This page was last revised on May 18, 2026. It was originally submitted on October 24, 2021, by Allen C. Browne of Silver Spring, Maryland. This page has been viewed 572 times since then and 46 times this year. Photos: 1, 2, 3, 4. submitted on October 24, 2021, by Allen C. Browne of Silver Spring, Maryland. • Mark Hilton was the editor who published this page.
