Near Relay in Baltimore County, Maryland — The American Northeast (Mid-Atlantic)
The Thomas Viaduct
Front
July 4th, 1833.
Finished,
July 4th, 1835.
Johnathan Knight,
Chief Engineer
Caspar W. Wever,
Superintendent of Construction.
Designed by
Benjamin H. Latrobe.
Built by
John McCartney of Ohio.
(Other two sides of the monument list company directors.)
Erected 1835 by Baltimore and Ohio Railroad.
Topics and series. This historical marker is listed in these topic lists: Bridges & Viaducts • Railroads & Streetcars. In addition, it is included in the ASCE Civil Engineering Landmarks, the Baltimore and Ohio Railroad (B&O), and the National Historic Landmarks series lists. A significant historical date for this entry is July 4, 1842.
Location. 39° 13.353′ N, 76° 42.777′ W. Marker is near Relay, Maryland, in Baltimore County. Marker can be reached from Railroad Avenue near Viaduct Avenue. It's quite a climb up from Railroad Avenue to track level where the marker is located. Viaduct is easier to approach on its southern end. Marker is at the northern end of the viaduct.
Southern end of the viaduct is in Elkridge in Howard County near the intersection of Lawyers Hill Road, River Road, and Levering Avenue. Approach southern end from U.S. Route 1 (Washington Boulevard), and Levering Avenue.
The viaduct crosses the Patapsco River and Patapsco Valley State Park. Viaduct is in the triangle formed by I-95, I-895 and I-195.
Northern end is half a mile from the St. Denis train station on the MARC Camden Line. The same roadway nearest the marker that is Railroad Avenue in Halethorpe continues straight into South Rolling Road, and straight again into Cedar Avenue. Cedar avenue can be reached from Clark Boulevard off Route 1.
The rail junction at the northern end of the bridge is called Relay, as is the adjacent neighborhood in Halethorpe. But there is no longer a Relay post office or zip code. Touch for map. Marker is in this post office area: Halethorpe MD 21227, United States of America. Touch for directions.
Other nearby markers. At least 8 other markers are within walking distance of this marker. A Rural Vacation Spot (about 300 feet away, measured in a direct line); Masterpiece of the Early B&O Railroad (about 300 feet away); During the Civil War (about 500 feet away); The Relay House (approx. 0.2 miles away); Patapsco Valley State Park (approx. 0.4 miles away); Elk Ridge Landing (approx. 0.4 miles away); World War II (approx. half a mile away); Great War (approx. half a mile away). Touch for a list and map of all markers in Relay.
More about this marker. This monument, like the bridge, was designed by Benjamin H. Latrobe II, an American civil engineer, best known for designing railway bridges. Once nicknamed "Latrobe's Folly," as many doubted the viaduct could support itself, it remains in use to this day, carrying far heavier loads than ever envisioned.
Regarding The Thomas Viaduct. This stone bridge over the Patapsco River is still in use today carrying CSX freight trains (Capital Subdivision) and MARC commuter trains (Camden Line) between Baltimore and Washington. The Thomas Viaduct was named a National Historic Landmark in 1964.
Also see . . .
1. Thomas Viaduct. Page on www.bridgemeister.com (Submitted on February 28, 2006.)
2. B&O Washington Branch Modern-Day Photo Tour. 1½ miles from Relay (the junction with the Main Line north of the bridge), across the bridge and south past Elkridge. (Submitted on February 28, 2006.)
3. Sidereal's Thomas Viaduct Slideshow. Nineteen vivid photographs of the viaduct itself. (Submitted on April 20, 2006.)
4. Library of Congress HABS/HAER entry for the Thomas Viaduct. Additional Thomas Viaduct information and pictures are available from this Library of Congress Historic American Building Survey (HABS) and Historic American Engineering Record (HAER) site. (Submitted on September 12, 2007, by Kevin W. of Stafford, Virginia.)
5. Impossible Challenge: The Baltimore and Ohio Railroad in Maryland. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
6. Impossible Challenge II: Baltimore to Washington and Harpers Ferry from 1828 to 1994. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
7. Royal Blue Line. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
8. Royal Blue Line: The Classic B&O Train Between Washington and New York. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
9. Baltimore and Ohio Railroad (Railroad Color History). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
10. Baltimore and Ohio Railroad (MBI Railroad Color History). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
11. Baltimore and Ohio's Capitol Limited and National Limited (Great Passenger Trains). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
12. Route of the National Limited (Baltimore and Ohio Passenger Service, Volume 1). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
13. Route of the Capitol Limited (Baltimore and Ohio Passenger Service, Volume 2). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
14. The Great Road: Building the Baltimore and Ohio, the Nation's First Railroad 1828 - 1853. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
15. Chessie System (MBI Railroad Color History). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
16. CSX (MBI Railroad Color History). (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
17. Baltimore and Ohio Cabooses Volume 1: Photos and Diagrams. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
18. B & O Caboose Diagram Book. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
19. Baltimore and Ohio in the Civil War. (Submitted on May 5, 2008, by Tom Fuchs of Greenbelt, Maryland.)
Additional commentary.
1.
Borrowing from ancient Roman technology this viaduct has stood the test of time and proven its value toward commerce and trade between the states. The stone that was used is cut and placed in a ashular mode and it appears that these stones were pre-cut and fabricated off site but in closer examination many of these stones had to be field dressed as this viaduct is not simply a straight line arched bridge but one that is curved with a radius employed in its construction. With this in mind the supporting truss members has a compound splay to accommodate this method. The surveying, the fabrication and engineering of this Roman arched viaduct has stood the test of time and upon visual examination the mortar joints are still very tight and they do not appear to have ever been repointed or repaired.
— Submitted January 12, 2008, by James W. Lawson Jr. of Rockville, Maryland.
2. Reading 2102
The steam locomotive in this picture was originally built by the Baldwin Locomotive Works in 1923 as an I-10a. The Reading Railway converted it to a T-1 in 1945.
— Submitted November 18, 2013, by Tom Fuchs of Greenbelt, Maryland.
Additional keywords. Baltimore and Ohio Railroad
Credits. This page was last revised on October 31, 2019. It was originally submitted on February 28, 2006, by Tom Fuchs of Greenbelt, Maryland. This page has been viewed 34,470 times since then and 3,852 times this year. Photos: 1. submitted on January 22, 2008, by Christopher Busta-Peck of Shaker Heights, Ohio. 2, 3, 4, 5. submitted on February 28, 2006, by Tom Fuchs of Greenbelt, Maryland. 6. submitted on October 11, 2006, by Tom Fuchs of Greenbelt, Maryland. 7, 8. submitted on January 3, 2007, by Tom Fuchs of Greenbelt, Maryland. • J. J. Prats was the editor who published this page.