Thomas Viaduct
The Thomas Viaduct spans the Patapsco River and Patapsco Valley between Relay, Maryland and Elkridge, Maryland, USA. It was commissioned by the Baltimore and Ohio Railroad (B&O); built between July 4, 1833, and July 4, 1835; and named for Philip E. Thomas, the company's first president. Some claim it to be the world's oldest multiple arched stone railroad bridge. However, the Sankey Viaduct on the Liverpool and Manchester Railway was opened in 1830, and finally completed in 1833.
Thomas Viaduct | |
|---|---|
| Coordinates | 39°13′18″N 76°42′48″W |
| Carries | Railroad |
| Crosses | Patapsco River |
| Locale | Elkridge, Maryland |
| Owner | CSX Transportation |
| Heritage status | NRHP 66000388 |
| Characteristics | |
| Design | Arch bridge |
| Material | Patapsco granite |
| Total length | 612 feet (187 m) |
| Width | 26 feet 4 inches (8 m) |
| Height | 59 feet (18 m) |
| Longest span | 58 feet (18 m) |
| No. of spans | 8 |
| History | |
| Designer | Benjamin Henry Latrobe, II |
| Constructed by | John McCartney |
| Construction start | 1833 |
| Opened | July 4, 1835 |
Thomas Viaduct, Baltimore & Ohio Railroad | |
| Area | 0.5 acres (0.20 ha) |
| NRHP reference No. | 66000388 |
| Added to NRHP | October 15, 1966 |
| Location | |
| References | |
At its completion, the Thomas Viaduct was the largest railroad bridge in the United States and the country's first multi-span masonry railroad bridge to be built on a curve. In 1964, it was designated as a National Historic Landmark. In 2010, the bridge was designated as a National Historic Civil Engineering Landmark by the American Society of Civil Engineers.
The viaduct is now owned and operated by CSX Transportation and still in use today, making it one of the oldest railroad bridges still in service.