Great Falls

Great Falls - originally muddy sediments in the ocean

pothole excavated in bedrock

George Washington's Potowmack Canal

Potowmack Canal lock

(click on images for larger versions)

• Geology of Virginia
• Potomac-Shenandoah River System
• Geology of the National Capital Region - Field Trip Guidebook (US Geological Survey Circular 1264)
• Trip 6: The Incision History of a Passive Margin River, the Potomac near Great Falls
• Historic American Buildings Survey
• Potowmack Company: Great Falls Canal & Locks, Great Falls, Fairfax County, VA
• Potowmack Company: Great Falls Canal, Lock No. 1, Great Falls, Fairfax County, VA
• Potowmack Company: Great Falls Canal, Lock No. 2, Great Falls, Fairfax County, VA
• Potowmack Company: Great Falls Canal, Locks No. 3, 4, 5, Great Falls, Fairfax County, VA
• National Park Service - Great Falls
• Potomac Conservancy
• "Last Chance Landscape" - Middle Potomac Scenic Corridor
• Teaching with Historic Places Lesson Plans: The Building of the Chesapeake and Ohio Canal

Topics to Explore

- why is there a waterfall at this location? Why would it ever move/disappear?
- where is the contact between metamorphic and sedimentary rocks, compared to Great Falls Park?
- how are potholes carved into bedrock?
- would you build a dam here? why, or why not?
- why are there ruins of an old canal in the park? why didn't the canal project succeed initially? why did it succeed later?