Sometimes the best-kept secrets are hidden in our own backyard. For example, if you were to ask an experienced caver from France to name 10 of the top technical caves in the world, he would more than likely include Neff’s Cave among them. He might even tell you where it is. He may have even been there. On the other hand, if you were to ask random Salt Lakers about Neff’s Cave, a majority of them would most likely respond with, “Neff’s Cave? Where’s that?”

In 1949, teenage brothers John and Jamie Lyon discovered a clandestine opening to a cavern at the base of a limestone cliff not far off Neff’s Canyon trail in the Wasatch Mountains just east of Salt Lake City. The average person may not have given this jagged crevice a second glance, but for these young adventure seekers, this portal to an underground realm was more temptation than they could resist.

The boys returned several times to the cave, each time pushing the boundary of their incursion. Eventually, they brought ropes, lanterns and sandwiches, prepared ― so they thought ― to truly explore this subterranean domain. But things didn’t go exactly as planned.

Now well inside the cave, John and some of his friends found themselves trapped at the bottom of a cliff face composed of crumbling shale where they spent three days immersed in total darkness.

They took turns crouching on the ground as the other boys huddled over them to share body heat. Their youthful exuberance, so palpable that morning, must have been smothered by the cold and clammy blackness that enveloped them now.

As they were about to give up hope of ever being found, a team of rescuers came, led by Jamie, who didn’t go to the cave with the other boys that day. He was the only person who knew where they might be. It seems they hadn’t bothered to tell any adults about the cave.

As word of the cave spread, steps were taken to keep people out. In 1951, a team from the National Park Service determined that it was too dangerous to be a Park Service attraction. It was subsequently gated by the Forest Service.

Situated deep under Mt. Olympus, Neff’s Cave descends 1,163 ft. (354 m) into the earth, making it the 15th deepest cave in North America and the second deepest cave in Utah. It sits directly on the Wasatch Fault and a river flows beneath it.

As a single, large vertical fissure, Neff’s provides a technical challenge for even the most intrepid spelunker. Helmets, ropes, rappelling and ascending gear, adequate lighting, and years of caving experience are required to fully explore its depths. It is no place for amateurs or the merely curious.  

In the early 1990s, I was fortunate to be part of a hand-picked team of intermediate to advanced cavers led by none other than John Lyon himself. We were treated to an initiatory exploration of Neff’s in exchange for hauling bags of cement up the mountain to reinforce the cave’s steel gate that had been breached by vandals.

One at a time, we inched our way down into the barely-penetrable darkness which was perforated only by the flashing blades of light from a half-dozen headlamps. There’s nothing quite as adrenaline-inducing as free-rappelling on a rope, 100 feet at a time, straight down into a black and seemingly bottomless abyss. It was a truly thrilling, once-in-a-lifetime experience that I’ll never forget.   

A sign on the gate reads, “Neff’s Cave is gated to protect delicate resources inside. It is protected by the Federal Cave Resources Protection Act of 1988. Permission to enter may be obtained by contacting the Wasatch-Cache National Forest, Salt Lake Ranger District.”

Only professional cavers need apply. For the protection of the cave and the potential for death or a complicated and expensive rescue operation, access to Neff’s Cave is highly restricted by the Forest Service and the Timpanogos Grotto of the National Speleological Society. You must be a member of one of these organizations or be endorsed and accompanied by a member in good standing to request entry.

If you are interested in Utah caves, read
Spelunking in Utah – Exploring the Vast World Beneath – Cavers Take Their Sightseeing Underground

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