It sounds crazy, but it is real, we’ve seen it ourselves.
The Dune That Moved
Long before the trail was created, the Walking Sand Dune was already famous — and in motion.
The Great Dune moved inland at such a steady rate it earned the nickname “Galloping Dune.” Locals called it the “Walking Sand Dune.”
Generations of local kids ran across the top of the 20-plus feet of loose dune, then — launched themselves off the top: running jumps, somersaults, arms-out tumbles on the way to the bottom. It was the kind of thing you just did if you grew up near Lewes.
The park trail system was also used by the Cape Henlopen High School cross country team for practices and meets.
The writers of a 1938 federal guidebook described what you could see from the top: the spires of Lewes, the great marshy flats of Gordon’s Pond, the long line of dunes down the coast to Rehoboth, and the Atlantic stretching out to the horizon. During the War of 1812, the dune provided a vantage point from which to observe the bombardment of Lewes by the British. In the 1930s, it served as a perch from which to watch boats search for the sunken DeBraak and its treasure.
For preservation purposes, ultimately grass, trees, and shrubs were planted to stabilize the sand, and the dune’s movement became far less noticeable. Hundreds of trees went into the ground — pitch pine, loblolly, scrub oak — anchoring the sand in place and slowly ending the migration that had defined the dune for centuries. The Walking Sand Dune had been stopped in its tracks.
The Trail Itself
The Walking Dunes Trail is a roughly 2.5-mile loop that takes you through wooded maritime forest, salt marsh wetlands, and open sand dunes. It is not a difficult hike, but it is a varied one — one minute you’re in dense pine forest with bunker vents poking up from the ground, the next you’re on open sand with the ocean visible in every gap between the trees.
But it’s actually more than a single trail. It connects to the Georgetown-Lewes Bike Trail and several other interconnected trails, many you can bike on, like we’ve seen former president Joe Biden biking on. nd
Start at the Fort Miles Historic Area parking lot and let the signage guide you. Stop at the Great Dune overlook. Spend time at the Artillery Park, where the park has assembled an impressive collection of the guns that once kept this coastline on alert. Battery 519, one of the original underground gun batteries, has been meticulously restored and now houses the Fort Miles Museum with interactive exhibits on the fort’s history — it’s worth every minute you give it.
If you’re bringing kids, this trail delivers in every direction: there’s still plenty of sand to climb, history to touch, towers to scale, and the very real feeling that something big once happened right here, underneath these quiet trees, in plain sight of the Atlantic.
What’s Under, Near, Next to the Trail
The possibility of German U-boats invading Philadelphia via the Delaware River led to the construction of Fort Miles in 1941 — a secret, state-of-the-art installation built within and around the massive natural sand dunes of Cape Henlopen State Park, providing perfect cover for an array of heavy guns capable of firing artillery rounds up to 25 miles.
The whole operation was deliberately invisible. It was said to have been not only highly secure, but highly secretive — described by one historian as “a huge fortress concealed deep in the sand dunes.”
Depending on where you are, that fortress may be right beneath your feet as you walk the trail today.
Here’s where it gets genuinely extraordinary.
Beneath the picturesque terrain of Cape Henlopen lie underground bunkers built to protect the United States from German invasion. A series of tunnels reportedly connects the bunkers, allowing the 2,500 soldiers stationed at Fort Miles to move undetected.
Walk the trail today and pay attention — there may be bunkers ucked into the dunes, sand and saltgrass pulled over them like a blanket. The above-ground buildings are low and deliberately unremarkable.
All of that secrecy. All of that preparation. Waiting for an enemy that never showed up.
The Observation Towers
Scattered across the Cape Henlopen landscape — and strung down the Delaware coast for 40 miles — stand the concrete fire control towers, and they are impossible to miss once you know what you’re looking for.
The towers were used in pairs to triangulate the large defense guns at Fort Miles. Soldiers could take readings on offshore targets, radio the coordinates to a gunnery room, and the calculations were converted into firing positions for guns on the ground. When two towers sighted the same target, a fix could be determined.
Delaware is the only state in the nation that still has all of its original fire control towers — eleven of them still standing. Five such towers exist within the current boundaries of Cape Henlopen State Park, including Tower 7, which has been restored for visitor access.
Once in the park, it’s free to climb.
Tower 7 is the one you want. The way up is 118 steep steel steps — a tight spiral that will make anyone with a fear of heights reconsider their choices, since you can see straight down through the staircase the entire way.
Back in the day? Locals would climb to the top of the open towers. The stairs were much smaller then, maybe 24″ wide.
Along the way, you’ll discover viewpoints from multiple levels. On clear days, you can see across the river and easily pick out the observation tower and the Cape May Lighthouse.
Make it to the top and the reward is a 360-degree panoramic view of the Delaware Bay, the Atlantic Ocean, the entirety of the fort’s operations, and the distant coastline — the same view soldiers scanned for periscopes and silhouettes in 1942.
The concrete structures were built in a hurry — one-foot-thick walls poured in just two weeks — and were designed to last about 20 years. They are now over 80 years old and still standing.
The Bottom Line
Cape Henlopen’s Great Dune trail is the rare kind of place that gives you nature and history simultaneously, each one making the other more interesting.
The perfect JMO experience.
A dune that was moved by war. A forest planted to sustain nature. A network of tunnels running beneath your feet. And a concrete tower that once watched for enemy submarines still standing tall, open to anyone willing to climb the steps and look out at exactly what the soldiers were looking at.
It’s Delaware’s most popular state park — and for good reason. Come for the view. Stay for the story.
Journey Moore Often — because sometimes the most extraordinary history is the kind buried just beneath the sand.