Philadelphia’s Mystical Wilderness

Cave of Kelpius: The Secret Sanctuary of America’s First Doomsday Cult

Philadelphia, Pennsylvania, United States

By the Wicked Cool Places editors · Published Thu, Mar 19, 2026 · Updated Fri, Aug 28, 2026

Why it’s cool

This enigmatic stone chamber was the 17th-century base for a group of German mystics who predicted the imminent end of the world.

Northeast Adventure

A dark, rectangular stone entrance to the Cave of Kelpius is surrounded by green foliage and white flowers.

Deep within the dense canopy of Philadelphia’s Wissahickon Valley lies a stone chamber that serves as a silent witness to a 17th-century quest for salvation. In 1694, a Transylvanian scholar named Johannes Kelpius led a group of forty men into these woods, convinced that the world was on the brink of total destruction.

These German Pietists didn't just come to Pennsylvania for religious freedom; they came to wait for the literal end of days.

Why It Stands Out

The "Cave of Kelpius" is the most tangible remnant of America’s earliest organized doomsday sect. Often referred to as the Wissahickon Hermits, the group lived a life of rigorous study and isolation.

They named their collective after a passage in the Bible’s final prophetic book, envisioning themselves as the faithful seeking refuge in the wild. While they awaited the apocalypse, they didn't just pray; they were pioneers of science and art.

They constructed a large tabernacle that featured what is arguably the first astronomical observatory in the American colonies, using their telescopes to scan the heavens for signs of the Second Coming. Though the world did not end in 1694 as they predicted, the monks remained.

They became a vital part of the early Philadelphia community, serving as healers, musicians, and legal advisors. The city also features Philadelphia's Magic Gardens, another unique local landmark.

The small stone structure that remains today is the subject of historical debate. While some believe it was the actual dwelling of Kelpius, others suggest it was a simple springhouse or a storage cellar for their scientific instruments and books.

This small stone chamber shares a sense of mystery with The Ramble Cave. Its mystical status was cemented in 1961 when the Rosicrucians, who view Kelpius as a founding figure of their tradition in America, erected a granite monument at the site.

Before You Go

The site sits in the southern end of Wissahickon Valley Park, a green expanse spanning some 1,800 acres. To find it, look for the trailhead at Hermit Lane.

The path leads past a historic residence known as The Hermitage; from there, a short off-shoot trail to the right brings you directly to the stone entrance. The structure once featured a chimney and fireplace, though these were removed decades ago.

Despite its proximity to the city, the area retains a rugged, secluded atmosphere that makes it easy to imagine the isolation felt by the monks three centuries ago.

Questions worth answering

What's the story behind this stone chamber?

Johannes Kelpius brought forty men here in 1694 to prepare for the apocalypse. They were German Pietists who spent their time in the Wissahickon woods studying science and waiting for the world to finish.

Is this actually where the leader lived?

The purpose of the small building is a point of contention among historians. Some say it was the home of Kelpius, while others think it served as a cellar for their books and telescopes.

How do we get to the site?

Leave your car on Hermit Lane and follow the path past the house called The Hermitage. A quick turn to the right from the main trail leads you to the entrance of the chamber.

What kind of experience should we expect?

It's an adventure through 1,800 acres of parkland that feels isolated despite being in Philadelphia. Our own editorial from there notes the rugged atmosphere makes the 17th-century history feel quite close.

Visit Snapshot

To reach the site, park on Hermit Lane and follow the Yellow Trail past the gate near The Hermitage. Look for the first right-hand off-shoot path; the cave is located just a few hundred feet ahead.

Alternatively, you can park at the top of Hermit Lane, walk toward the baseball fields, and follow the fence line of the first field into the woods to find the lower-level path leading to the cave. On digital maps, the location is often listed as Hermit Cave.

Location

Philadelphia, Pennsylvania

Know before you go

Park along Hermit Lane and walk along Yellow Trail, past the trail gate near The Hermitage. Take the first right off-shoot and it will be just a few hundred feet straight ahead to your right, you can't miss it.

If you are still struggling to find it, the exact location is marked on google maps as 'Hermit Cave.' Alternate access: park near top of Hermit Lane, walk down toward baseball fields. Walk along the first base line fence of the first baseball field.

Enter the woods to the left, and follow the path walking back the direction you just came but at the lower level. Continue walking away from baseball fields for a while and the cave will be in front of you.

Editorial source

Cave of Kelpius

Tucked away in a remote section of Philadelphia’s Fairmount Park, you’ll find the “Kelpius Cave,” an enhanced cave built into the side of a hill, with a stone frame entrance marking what's believed to be the 17th century home of America’s first cult of mystics to predict the imminent apocalypse. Although cynics suspect the structure is simply an old springhouse, tradition holds that this area along the banks of Wissahickon Creek was settled in 1694 by mystic and scholar Johannes Kelpius and his followers.

Believing, based on elaborate interpretation of the Bible's "Book of Revelation," that the world was going to end that year, the monks sought to live a solitary lifestyle in the wilderness while awaiting the End of Days and the Second Coming. The group was known as “Hermits of the Wissahickon,” or “The Society of the Woman of the Wilderness"—the latter a reference to a passage in "Revelation” in which a woman flees to the wilderness to seek refuge from the end of the world.

Following this example, the monks (all of whom were men) established themselves on a hill at the edge of the Wissahickon woods. The area was known as Hermit's Glen; today, a nearby road called Hermit Lane gives a nod to the area's occult history.

These early Pietist monks fled their home country of Germany to the newly founded province of Philadelphia, which was built on the principle of religious tolerance and which already had a large Quaker population. (There is a statue of a man in Quaker garb called “Toleration” in the Wissahickon as well, 40 minutes north of the cave by foot, that watches over the valley).

Kelpius, Philadelphia’s first mystical guru, hailed from Transylvania and was 26 years old when he formed the Society here in the woods. He was a musician, scholar and writer, interested in botany and astronomy.

Indeed, many of the monks practiced medicine and composed music while waiting out the end of days. They're thought to have lived in cabins scattered along the river, and used the cave to store books and scientific equipment.

The group of 40 monks—40 was believed to have a mystical significance—also erected a 40-square-foot tabernacle. The meeting space included a rudimentary observatory where monks practiced astronomy, thought to be the first observatory in the new world.

Unfortunately all that remains is the small stone structure near the location where the tabernacle used to stand, the woods around and above it beautifully overgrown and wild. When the end of the world did not come as planned, Kelpius and the monks stayed in the Wissahickon, creating art and music, studying the skies, and helping the community around them when they could.

The group mostly disbanded after Kelpius’s death in 1708, though many stayed in the community as doctors and lawyers. One of the later members of the Society, Christopher Witt, painted the first oil painting in America, with Kelpius as his subject.

The painting is currently housed at the Historical Society of Pennsylvania. Until the 1940s, the structure dubbed Cave of Kelpius had a fireplace and chimney, which were removed due to vandalism, but do hint at its having been more than a springhouse.

The cave's true identity has been debated for many years. It's marked today by a granite monolith placed outside the entrance in 1961 by the Rosicrucians (meaning "rose" and "cross"), a worldwide mystical brotherhood that claims to have secret wisdom dating to ancient Egypt, and considers Kelpius the original American Rosicrucian.

Today, you'll find the enigmatic structure located on the trails near the southern end of the 1,800-acre Wissahickon Valley Park, a section of Fairmount Park in Northwest Philadelphia.

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