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Seneca Mill and Quarry

National Park Service Historic Site

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The Seneca Mill and Quarry ruins are located along Seneca Creek, near the Potomac River. The quarry is renowned for providing the signature red sandstone used to build the Smithsonian Castle. The property includes ruins of the stonecutting mill, located at the Junction of Seneca Creek and the C&O Canal, just NW of the aqueduct and the restored quarry master's house, located within Seneca Creek State Park. Access to the mill and quarry ruins is from the Seneca Aqueduct and Riley's Lock Road. A trail leads to the mill from the upstream side of the aqueduct.

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Contact Information
C&O Canal National Historical Park
142 W. Potomac St., Suite 100
Williamsport MD 21795