Patapsco Valley

Patapsco Valley
Patapsco River Valley
McKeldin Rapids, McKeldin Recreation Area
Patapsco Valley Location of the Patapsco Valley in Maryland
Location	Anne Arundel County, Baltimore County, Howard County, Carroll County, Maryland
Floor elevation	260
Long-axis direction	North-South
Long-axis length	39 miles (63 km)
Geography
Bounded by	Elkridge Landing(south) Liberty Reservoir (north)
Coordinates	39°17′N 76°47′W / 39.29°N 76.78°W / 39.29; -76.78Coordinates: 39°17′N 76°47′W / 39.29°N 76.78°W / 39.29; -76.78
Population centers	Brooklyn Park Catonsville Ellicott City Elkridge Lansdowne Linthicum Marriottsville Daniels Hanover Sykesville Woodbine
Traversed by	Interstate 70 Interstate 95 Metropolitan Boulevard (I-195) Harbor Tunnel Thruway (I-895) Annapolis Road (MD 648) Belle Grove Road (MD 170) Frederick Road (MD 144) US Route 40 Nursery Road Rolling Road (MD 166) Old Court Road (MD 125) Montgomery Road Old Washington Road (MD 97) Sykesville Road (MD 32) Woodbine Road (MD 94)

The Patapsco Valley is a small valley surrounding the Patapsco River in central Maryland. The region is known for its historical significance as a major economic and industrial center in the eighteenth and nineteenth centuries.

The Patapsco Valley follows the Patapsco River, a major river flowing into the Chesapeake Bay. The valley is mostly wooded with various steep elevations as the valley travels north. The valley begins in Elkridge Landing and runs north through a number of mill town communities until the river splits into two segments. Liberty Dam and its reservoir, located on the North Branch, is a major component of the Baltimore city water system. Besides Baltimore, the river also flows past Ellicott City (the county seat of Howard County) and Elkridge. The South Branch of the river flows east from its source in Marriottsville, Maryland.

Patapsco Valley State Park is adjacent to 32 miles (51 km) of the Patapsco and its branches, encompassing a total of 14,000 acres (5,700 ha) in five different areas. The river cuts a gorge 100–200 feet (35–70 m) deep within the park, which features rocky cliffs and tributary waterfalls.

The valley contains the communities of Catonsville, Ellicott City, Elkridge, , Daniels, Hanover, and many others.

The valley is drained by the Patapsco River and its tributaries.

John Smith was the first European to explore the river noting it on his 1612 map as the Bolus River. The "Red river", was named after the clay color, and is considered the "old Bolus", as other branches were also labelled Bolus on maps. As the river was not navigable beyond Elkridge, it was not a major path of commerce with only one ship listed as serving the northern branch, and four others operating around the mouth in 1723. The Patapsco valley was used as the route of the Baltimore and Ohio Railroad's original main line west constructed from 1829 onwards, and this route remains, though much altered. Many old railroad bridges were constructed in the valley, most notably the Thomas Viaduct and the Patterson Viaduct, of which ruins remain. Flour mills and a hydropower dam were formerly powered by the river.