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Mount Vernon to Reagan Airport

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St. Marys River

Maryland Tributary

This historic river flows 22.3 miles through southern St. Mary's County, Maryland. The river is 2 miles wide at its mouth and was an attractive spot for early settlers in Maryland. The colonial settlement became the first capital of Maryland and now features a large state historic area. The upper part of the river is the site of St. Mary's River State Park, which includes a 250-acre lake.

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Contact Information
Maryland Department of Natural Resources