• dogwood across creek

    Prince William Forest

    Park Virginia

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  • Firewood

    Outside firewood is prohibited in Prince William Forest Park, unless it is certified USDA 'bug free' firewood. Dead and downed wood may be collected from designated areas for use while in the park. Help us protect the forest from invasive species!

  • Warm Wet Spring = More Ticks

    Please check yourself and your pets for ticks continually during and after your visit. Ticks are less prevelent if you stay on trail or in mowed areas. Wearing light colored clothing helps you spot them before the attach.

  • Temp. Closure C-Loop Bathroom

    Due to sequestration cuts, the C-Loop bathroom at Oak Ridge Campground will remain closed. Please use the B-Loop restroom, a short walking distance away. We apologize for the inconvenience.

Geologic Formations

Cascades along the fall line
 
Prince William Forest Park's Geologic Past
It is hard to imagine that this area was once the home of numerous volcanoes. Perhaps it is even harder to believe that the ground you are now standing on was at one time merged with the African continent. If you were suddenly transported 150 million years back in time to this same spot, you might find yourself next to a dinosaur four stories tall. How do we know this? How can we say what the earth was like a million or even a billion years ago? The answer lies literally, right under your feet. The rocks found throughout Prince William Forest Park contain important clues that record 570 million years of geologic history. To learn more, read the park's Geologic Resources Inventory Report.
 
geology formation

south valley trail. NPS Photo.

Geology E--Walk
Take a journey through of geologic past on our Geology E-Walk, a stop by stop tour of some of the park's most interesting geologic formations.

 
petrock150

Petrified Wood
Learn about the 150 million year old piece of petrified wood found in front of the visitor center. Discovered in the early 1960s, during the construction of Interstate 95, the petrified wood specimine is one of the largest ever discovered in the Commonwealth of Virginia.

 

Did You Know?

Office of Strategic Service (OSS) recruits learning Morse code during the Second World War

Prince William Forest Park was used by the Office of Strategic Services (forerunner to the CIA) as a training camp for spies during World War II.  Today, you can rent a cabin where spies once learned their trade.