Seneca Quarry

The abandoned Seneca Quarry, located along the C&O Canal in Montgomery County, MD, once provided the distinctly rusty red sandstone used to construct not only the Smithsonian Castle, but also hundreds of other buildings in the Washington, D.C. area. Winter is the ideal time to visit the quarry:  leaves are off the trees, providing visitors with an unobstructed view of this incredible site. Join Garrett Peck, author of The Smithsonian Castle and the Seneca Quarry, for a tour of this historic property, which includes the Seneca Aqueduct, a former stonecutting mill, and the restored redstone quarry master's house.  After venturing through the quarry, the tour will continue to Bull Run, site where stone for the Smithsonian Castle was obtained. 


The tour covers 1.5 miles round trip and includes a steep climb up the quarry walls and down through a rock garden.  Much of the route to and from the quarry will be wooded along deer paths. 


Wear boots and dress in warm layers. Pack a snack and bring bottled water. Port-a-Johns available. A signed waiver is required for each participant.


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Available for private or group bookings.  Contact us for details.

Approximately 3 hours
Reservations required.

Available for private or group bookings.  Contact us for details.

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Embarks from the C&O Canal Seneca Aqueduct parking lot at the terminus of Riley's Lock Road, Seneca MD.
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