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Remembering the Seneca Quarry

By Mark S. Kuhar

If you’ve ever seen the Smithsonian Institution in Washington, is hard not to notice the beautiful red stones that were used to construct the building. The story of those stones is just as remarkable as that of the building they grace.

The source of the red stones was the nearby Seneca quarry. The quarry saw its first developer die, filed for bankruptcy twice, suffered through floods and contributed to a national scandal that embarrassed the Grant presidency and helped bring down the Freedman's Bank.

The untold history of the quarry, its owners, the emancipated slaves who toiled there and the historical context connected with the site intrigued author Garrett Peck enough to write the book The Smithsonian Castle and the Seneca Quarry, which has just been published by The History Press.

“It was a lot of fun researching this book, and incredibly rewarding to find archival evidence of the quarry's impact on the region,” Peck told Rock Products. “Like finding the C&O Canal toll records of the first two boats that carried Seneca redstone for the Smithsonian Castle project, or finding an 1823 payroll from the quarry that clearly showed the use of slaves. Or finding a treasure trove of photos showing the quarry in operation.

“What was amazing is that there were numerous quarries along a mile-long stretch of the Potomac River west of Seneca Creek,” Peck said. “They were widely used for construction sites all around the DC area, especially once the C&O Canal opened at Seneca in 1833, allowing the stone to get to downtown in a day. It was a waterborne highway long before we had flatbed trucks to carry the stone. And as everyone knows, stone is pretty darn heavy.

Peck leads tours to the Seneca quarry site, and it is a surprise to him how fascinated people are about quarries – especially once they can associate it with a piece of architecture or part of familiar history.

The quarry site is located along the C&O Canal near Seneca Aqueduct, and most people bike or hike right past without noticing it. The quarry is covered with impenetrable forest and thick brush. Winter is the ideal time to visit, when the quarry is actually accessible.

“It's an impressive site: along this one-mile stretch of the Potomac there were numerous redstone quarries, worked by the Peter family of Georgetown until 1866. Visitors can see the 1853 fence piers from Lafayette Square that were dropped off at the quarry in 1999, then venture into the quarry and see the visible remains of chisel and iron rod marks, steel anchors for the numerous derricks, and the restored quarry master's house that still stands above,” Peck told the Huffington Post, in a separate interview.

Just to the west of Seneca quarry is the Bull Run quarry, where quarry owner John P.C. Peter dug the stone for the Smithsonian Castle. He won the contract to supply redstone for the Castle, then died in January 1848 of lockjaw less than a year into the project. The Kiplinger family now owns Peter's nearby home, Montevideo, and has beautifully restored it.

The Seneca Sandstone Co. purchased the quarry after the Civil War. It was a financially mismanaged and undercapitalized company that had attempted to influence-peddle by selling stock to senior Republicans for half price – including to Ulysses S. Grant. When it went bankrupt in 1876, the Seneca quarry helped bring down the Freedman's Bank. This forgotten chapter in American history became known as the Seneca Stone Ring Scandal, a scandal that none of Grant's biographers previously covered.

“Given how important the Seneca quarry is to U.S. history, I've often wondered why we don't have a quarry visitor park, and I advocate for such a park in the book,” Peck wrote.

Garrett Peck is a historian and literary journalist. He is the author of three other books: "The Prohibition Hangover: Alcohol in America from Demon Rum to Cult Cabernet;" "Prohibition in Washington, DC: How Dry We Weren't;" and "The Potomac River: A History and Guide." You can find out more at

To purchase the book, go to