Off-the-Path Hike to Seneca Quarry - Atlas Obscura

Poolesville, Maryland

Off-the-Path Hike to Seneca Quarry

Join us for a guided hike through the ruins of Seneca Quarry, a site with ties to a presidential scandal and the Smithsonian Castle.

Hike into geological, architectural, and presidential history at Maryland's lost Seneca Quarry with celebrated guide Garrett Peck.

On this two and a half hour walking tour, we’ll make our way along unpaved trails to view the ruins of Seneca Quarry, notable for producing the distinctive red sandstone used for the Smithsonian Castle and many other D.C. buildings. It was a focal point in a presidential scandal when the quarry's owners' questionable business practices embroiled President Grant in what became known as the Seneca Stone Ring Scandal.

Our guide for this adventure will be historian and author Garrett Peck. He's been featured on the History Channel, C-SPAN and has presented to institutions across the nation's capital.  He recently wrote a book about the Seneca Quarry titled  The Smithsonian Castle and the Seneca Quarry.

Peck will bring us to the ruins of the quarry’s old stonecutting mill, Seneca Aqueduct, and the quarry master’s house. We will also enter the quarry to see the visible remains of the numerous derricks and the 1853 fence piers from Lafayette Square that were left at the quarry. Peck will enlighten us on the past, present, and future of this historic red sandstone quarry. 


  • This location is not metro or bus accessible and located about 45 minutes outside of Washington, D.C.
  • Please map your route in advance to give yourself enough travel time.
  • Parking is free and available at the parking lot adjacent to Riley’s Lock, at the very end of Riley's Lock Road.
  • This is a 2.5 hour, outdoor walking tour on unpaved trails. Wear appropriate, closed-toe footwear and dress for the weather. 
  • All participants must complete the liability waiver that will be sent prior to our adventure.
  • Photography is allowed.
  • This adventure is family and dog-friendly, but adventurers under 18 must be accompanied by an adult. Physical restrictions apply.


This event is part of a series of Chase Sapphire Selected experiences.  Questions or concerns about this experience? Email for help.

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Advance tickets only. All sales final. No refunds or exchanges.