Caledon State Park

Had this tree fallen the other way, it would have blocked the trail guides use for the eagle tour. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Boyd's Hole Trail takes you from the visitors' center to the Potomac River waterfront. In the colonial era, Boyd's Hole was a port that remained active until the Civil War. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Along the Boyd's Hole Trail, an invasive species grows in an area where the foundation of what's believed to be an early tobacco plant sits. The plantation was active from the 1600s to the 1800s. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Maryland is seen on the other side of the Potomac River. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Along the trails, you'll see natural beauty like this. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

It's not uncommon to see dragonflies, butterflies and hummingbirds at the park. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Fern Hollow Trail is one of the easiest to hike at Caledon State Park. It's just over 1 mile long. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Ferns really do grow along Fern Hollow Trail, one of Caledon's 10 hiking trails. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Throughout the heavy-growth forest, trees are down. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Some trees in Caledon are 100 feet tall. Eagles nest in trees in the marshy areas of the park that are off-limits to the public. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Here's a close-up of the roots of one of the trees down along a trail in the park. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Most of the trails are easy to moderate in difficulty. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Even in old dead trees, new growth emerges. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledon State Park includes a number of different types of trees. It's a National Natural Landmark. Here, the roots of a fallen tree are seen. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Berries grow naturally along the trails. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledon State Park is home to a lot of different types of animals. Some are mounted in the visitors center. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

The park has an estimated 150 species of birds, as well as a dozen types of frogs, according to the tour guide. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

A fox is among the animals on exhibit at the visitors center. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Caledon State Park in King George, Va., is about 60 miles from D.C. Take the Governor Harry W. Nice Memorial Bridge from Maryland into the Northern Neck of Virginia to get there. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Picnic facilities at the park include an amphitheater with picnic tables and a fireplace. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledon State Park is a daytime park, but offers a number of summer programs, including sunset kayak trips and kayaking to see eagles. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledron State Park does have a piece of Americana you don't see in many places these days. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Alex Bortner, a Caledon State Park tour guide, says it's not unusual for there to be two or three generations of eagles at the park. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledon State Park offers eagle tours on summer weekends and July 4. On the eagle tour, people watch an eagle flying along the Potomac River Saturday, June 29, 2013. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Fish in the Potomac River make up a major part of the diet of the eagles at Caledon State Park. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

An eagle, which can't be seen in this photo, perches in a tree, scanning the Potomac River for food. Those on the tour could see the white top of the eagle's head before it flew out over the water. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledon State Park has one of the highest concentrations of eagles on the East Coast. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Alex Bortner, tour interpreter, sets up a high-powered scope to see eagles in the trees at Caledon State Park. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Caledon State Park sits on 3.5 miles of the Potomac River. The nesting of eagles was discovered after Ann Smoot gave the property to Virginia in 1974. It had been in the Smoot family since the 1600s. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Driftwood is seen along the shore of the Potomac River at Caledon State Park. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Eagles use large branches to build their nests at Caledon State Park. Here is a replica of what a nest would look like. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Baby eagles double in size every day for a week after they are born. What young eagles don't know by instinct is how to hunt fish. They have to learn how to grab the fish and not end up in the water. The angle and power with which an eagle grabs a fish kills the fish instantly, tour guide Alex Bortner says. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

Eagles live 15 to 20 years. As they mature, the feathers on their head turn white. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

While there's no guarantee that people on the eagle tour will see eagles, one could be seen from the cliffs high above the Potomac River. Sorry, it's not captured in this photo. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher

The talons of an eagle are so strong they exert 500 pounds of pressure, compared to 200 pounds for a human hand. The talons of eagles change color as they mature. This is the talon of one of the mounted eagles in the visitors center at Caledon State Park. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

This eagle on display at Caledon State Park is about 4 1/2 years old. Eagles are hollow-boned. Their skeletons weigh less than 1 pound, while their overall weight is 15 to 20 pounds, with females larger than males. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

The eagle population in the U.S. declined dramatically in the 1970s when the now-banned pesticide DDT was used. DDT would build up in the fat of fish eaten by eagles and would weaken the shells of unhatched eagles. Eagle populations are now on the rise. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

The other eagle on display at Caledon State Park is 3 1/2 years old. Eagles mate when they are 4 1/2 to 5 years old. During courtship, a female eagle will lock talons with a male and drop from the sky. If the male fights her, she lets him go. If he drops with her, he survives what tour guide Alex Bortner calls the "test of bravery" and they become a couple. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Access to parts of Caledron State Park is restricted so that the eagles are not disturbed. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

You can get to the beach areas to look for the eagles either by the tour's van or by walking or running along the park's trails. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Once along the water, you may find it hard to get by some of the trees. (WTOP/Ed Kelleher)

WTOP/Ed Kelleher

Caledon State Park has trails for hiking and biking. It also has a program called "Birking," where you can go bird-watching while mountain biking. (WTOP/Colleen Kelleher)

WTOP/Colleen Kelleher