Cape Henlopen State Park

"Cape Henlopen State Park is home to some of Delaware’s most pristine beaches, wild seaside forests, and flowing dune landscapes. Each summer, throngs of visitors flock to the state park to enjoy a day in the sand, surf-fishing, or a bike ride along one of the many paved paths that traverse the 5,200 acre park. Few realize that buried beneath the picturesque terrain are a series of underground bunkers built to protect the U.S. from German invasions during World War II.  The park’s original founding dates back to 1682, when William Penn established it as some of the first public lands in the original American colonies. Flash forward to 1941, when the fear of German U-boats invading Philadelphia via the Delaware River led to the formation of Fort Miles. Secret, state-of-the-art installations built within the massive natural sand dunes provided the perfect cover for an array of heavy guns that were capable of firing artillery rounds up to 10 miles. A series of tunnels reportedly connects the bunkers, allowing the 2,500 soldiers that were stationed at Fort Miles to move undetected.  While the site was officially decommissioned and transferred to the Delaware State Park system in 1964, the abandoned bunkers remain.  Access to the tunnels is limited only to the park officials; some bunkers are used as storage by the Parks Service while others lay empty and unused.  Above ground, WWII-era watchtowers are scattered across the landscape. Today, visitors can climb the 100-plus stairs to take in the picturesque panorama of the Cape from a lookout point once used to spot German U-boats." - ATLAS_OBSCURA