The 150-foot-high cliffs along the Potomac River, formerly the sea floor, provided just the right set of circumstances for the fossilization of animal remains. Fossilized remains indicate a sea filled with primitive shark-toothed porpoises, salt-water crocodiles, sea cows, gopher turtles, rays, whales, and sharks. Thousands of shark teeth found along this area of the Potomac attest to the frequency of the sharks, largest among them being the Giant White Shark, with teeth measuring seven inches or more.

Following your tour of the Great House and gardens or by the purchase of a grounds pass, we invite you to take a stroll along the beaches, search for sharks’ teeth, and enjoy the serenity of the water’s edge.


Rocks, Time & Fossils Video Series

Frequently Asking Questions by Jon Bachman, Education & Public Outreach Manager