Tulip Tree
ParkMaryland, US
Relay
Relay, Maryland is a historical gem where railroad history and natural beauty converge.
About
Relay, Maryland is a historical gem where railroad history and natural beauty converge.
This historic district, nestled in the picturesque Patapsco River Valley, offers a fascinating journey into America's early railway heritage, anchored by the magnificent Thomas Viaduct. Visitors can explore the significant landmarks that tell the story of a town born from the Baltimore & Ohio Railroad, providing a unique blend of architectural marvels and serene natural landscapes. It’s a destination that appeals to both history enthusiasts and those seeking outdoor recreation.
The crowning jewel is the Thomas Viaduct, an engineering marvel that continues to carry active rail traffic nearly two centuries after its construction. Beyond this iconic bridge, the area provides access to the Patapsco Valley State Park, inviting exploration of its scenic trails, river views, and diverse flora and fauna. Historical markers throughout the district paint a vivid picture of Relay's pivotal role in national transportation and even the Civil War.
Relay is an unforgettable visit for anyone interested in the foundational history of American infrastructure, offering tangible connections to the past amidst beautiful surroundings. Whether you're capturing the grandeur of the viaduct, hiking along the Patapsco River, or simply soaking in the historical atmosphere, Relay provides a rich and engaging experience. Be ready to snap and learn! Get the Snappit app to identify any nature species you find here.
Relay, Maryland, holds a unique place in American history as the first town established by a U.S. railroad, officially formed in 1830. Its name originates from its function as a "relay" point where horses were exchanged for the final leg of horse-drawn train journeys between Baltimore and Ellicott's Mills. The initial structure, the Relay House, served as a vital hub, including a hotel, restaurant, and stables. The area quickly grew in prominence, especially with the construction of the Thomas Viaduct between 1833 and 1835, which allowed the B&O Railroad to expand its reach and connect to Washington D.C.. The Thomas Viaduct, named after the B&O's first president, Philip E. Thomas, became the largest railroad bridge in the United States upon its completion and was the country's first multi-span masonry railroad bridge built on a curve. Its strategic importance was underscored during the Civil War when Union troops heavily guarded it to protect the crucial rail link between the nation's capital and the Union. Later, the elaborate Viaduct Hotel was built in 1872, serving as a showcase combination hotel and station until its closure in 1938 and demolition in 1950. Today, Relay is a historic district within Halethorpe, Maryland, and continues to draw visitors with its preserved landmarks and rich railway legacy.
What to do here
Walk to and around the Thomas Viaduct for stunning views and photographic opportunities. Explore the nearby trails along the Patapsco River. Read the historical markers to learn about the town's past. Observe active trains crossing the viaduct, a living piece of history.
Seasonal info
Spring: Mild temperatures, blooming wildflowers in the park, good for hiking.
Summer: Can be hot and humid; best for early morning or late afternoon visits.
Fall: Crisp air, beautiful fall foliage in the Patapsco Valley, excellent for photography and hiking.
Winter: Colder temperatures; snow can offer picturesque views of the viaduct, but trails may be icy.
Accessibility
The area around the Thomas Viaduct likely has some accessible viewing points. However, trails within Patapsco Valley State Park can vary in difficulty, and some historical areas might have uneven terrain. It's advisable to check specific trail conditions for accessibility.
Don't miss
1
Thomas Viaduct
An active, historic railroad bridge, a National Historic Landmark, and a National Historic Civil Engineering Landmark.
2
Obelisk
A 15-foot obelisk stands at the Relay end of the viaduct, commemorating its construction.
3
Patapsco River and Valley
Scenic views and access to trails within Patapsco Valley State Park.
4
Historical Markers
Various markers throughout the area detail Relay's railroad history and significance.
Wildlife you might spot
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Snap map for this place
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Good to know before you go
Wear comfortable shoes suitable for walking and potential uneven terrain, especially if exploring trails.
Bring a camera to capture the impressive architecture of the Thomas Viaduct and the scenic Patapsco River Valley.
Consider packing water and snacks, particularly if you plan on extended exploration of the adjacent state park trails.
Check local train schedules or use a train tracking app if you're hoping to photograph trains crossing the viaduct.
Visit historical markers and interpretive signs to fully appreciate Relay's rich past.
Be respectful of private property, especially when viewing historical buildings like the former Relay House.
Frequently asked questions
- The Thomas Viaduct is a historically significant railroad bridge in Relay, Maryland, notable as the first multi-span masonry railroad bridge in the United States built on a curve and the largest in the nation upon its completion in 1835. It is also one of the world's oldest railroad bridges still in use and played a crucial role in American railroad history and during the Civil War.
- Yes, the Thomas Viaduct in Relay, Maryland, is still an active railroad bridge operated by CSX Transportation, carrying freight and passenger trains daily between Baltimore and Washington, D.C. This provides visitors with the unique experience of seeing modern rail traffic traverse a nearly 200-year-old engineering marvel.
- Yes, Relay, Maryland, is located in the Patapsco River Valley and provides access to Patapsco Valley State Park, which offers numerous hiking trails and scenic natural beauty. The area is a popular destination for recreation and exercise enthusiasts.
Recent snaps at this place
Jun 5, 2026
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Photo attribution
(c) Alex Abair, some rights reserved (CC BY)
License: CC BY 4.0 ↗
Image may be shown cropped inside the card frame.
Jun 8, 2026
Jun 7, 2026
Jun 7, 2026
Jun 7, 2026
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