Thomas Viaduct

The Thomas Viaduct, completed in 1835, was so important it was guarded by Union troops throughout the Civil War./Howard Co. Tourism

The Patapsco River Valley provided the canvas for many of Maryland’s notable achievements. Here are a dozen milestones you probably didn’t know about and some locations you can still visit.

The first successful steam-powered boat in Maryland was John Ellicott’s boat designed to clear millraces that took to the water in 1789. It preceded Robert Fulton’s Clermont by 18 years and was one of a number of special-use steam craft around the country that preceded Fulton’s boat.

Benjamin Banneker of Ellicott’s Mills became the first Black astronomer and almanac publisher in America in 1792. George Ellicott encouraged Banneker’s study of astronomy. Banneker, largely self-taught, built a clock by the age of 20, and helped survey the city of Washington D.C. Benjamin Banneker Park is located in western Baltimore County near present day Ellicott City and includes a museum with exhibits about Banneker, a children’s discovery zone, a Sky View computer zone, live animals and a natural history display.

The Union Manufacturing Company (later the Dickey Mill in Oella) became the first textile mill in Maryland in 1811 and was the largest cotton works in America at the time.

The Ellicott brothers, who gave their name to Ellicott’s Mills (now known as Ellicott City), were also the makers and users of the first mobile home in America. It included a kitchen and was used to support work on the National Road in 1816.

19-10 Howard BO Railroad Musuem CAboose.jpg

This caboose is part of Ellicott City’s B&O Railroad Museum. The depot is the oldest in the United States./Howard Co. Tourism

Ellicott’s Mills became the first commercial railroad terminus in America in 1830, when the Baltimore & Ohio Railroad completed its tracks connecting Baltimore with the first railway depot in the world at Ellicott’s Mills. The railway depot, built in 1831, is the oldest surviving railroad station in America. It first handled only freight, but began serving passengers in 1857. You can visit the depot and museum at the foot of Main Street in Ellicott City. Explore the freight agent’s living quarters on the first floor and the Provost Marshall’s Office, Telegraph/Ticket Office, Men’s Waiting Room, and Car House on the second floor. A separate Freight House includes an HO-scale model of the first 13 miles of track from Baltimore to the site. There’s also a 1927 Caboose that once operated on the B&O.

Andrew Jackson was the first U.S. president to ride a train while in office, when he rode from Ellicott’s Mills to Baltimore in 1833.

Further expansion of the railroad was made possible in 1835 by the Thomas Viaduct, the world’s first multi-arched, curved stone railroad bridge. The bridge spans the Patapsco River and Valley and was the largest railroad bridge in the country when completed. The Thomas Viaduct made possible train travel to Washington D.C. and was guarded by Union troops throughout the Civil War. It followed the successful construction of the Carrollton Viaduct, the first railroad bridge built in America, which was completed in 1829. Both are National Historic Landmarks and still in use today. You can view the Thomas Viaduct by parking at the Avalon area contact station in Patapsco State Park and walking down the road, but don’t approach the bridge or tracks!

James Polk became the first president to ride a train to his inauguration in 1845, when he rode from Relay to Washington D.C.

The B&O Railroad built the first hotel for the exclusive use of railroad patrons in 1873, when it completed the Viaduct Hotel in Relay, also known as the Relay House. The hotel closed in 1938 and was demolished in 1950.

Patapsco Valley State Park became Maryland’s first state park in 1907 when a farmer donated 43 acres to the state. Today, the park extends along 32 miles of the Patapsco River, encompasses 16,000 acres, and offers five developed recreational areas. Along the park’s trails, especially in the Avalon and Orange Grove areas, you’ll see many historical sites and ruins that have survived severe flooding over the years.

The Bloede Dam, built in 1907, was the world’s first underwater hydro-electric plant and one of the earliest dams constructed of reinforced concrete. The electric plant was closed in 1924 because of competition from larger plants, but the dam remained a blockage on the Patapsco River until 2019 when its removal was completed, freeing about 60 miles of habitat for migratory and resident fish.

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