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The Danger: Flash Floods
Spry Canyon, Zion National Park, UT
The hike Ready to take your canyoneering skills to the next level? Spry Canyon gives hikers plenty of ropework practice, with 11 rappels scattered along the three-mile slot. And it’s relatively easy to reach: The route starts a third of a mile east of the main tunnel, where Pine Creek hits UT 9. After a half-mile hike north along Pine Creek’s wide, sandy wash, the route climbs over slickrock ledges and bowls to the pass between East Temple and Twin Brothers, then drops down to the mouth of Spry, where towering walls of orange-red sandstone signal the start of the slot.
The first rappel is down slabby sandstone, but subsequent raps dangle hikers over vertical cliffs. Swims are brief and infrequent (dry seasons may present just one pool, near the end). The final descent is the best: The 90-foot drop over Navajo sandstone lands hikers in lower Pine Creek, where it’s a short walk to the bridge a half-mile east of Canyon Junction (leave a car here for your return).
The risk The same pourovers that—when dry—make Spry a canyoneering playground become spine-crushing waterfalls after a rainstorm, when the terrain funnels water over the 40-foot dropoffs. Other slots may act as drainages for greater quantities of water than Spry, but few grow as Niagara-like with just one inch of rainfall—which is what fell in just 30 minutes the day Joe Cain and his two partners hiked down this four-foot-wide canyon. Cain had checked (and double-checked) the weather forecast, which called for a 30-percent chance of showers after noon, but figured they’d be through the slot by lunch. They almost were—but not before a wall of churning mud hammered down upon them from above.
Cain soared over a 40-foot dropoff; his friends continued over a second, larger spillway where the water’s force recirculated them for minutes at a time. When they did surface, a two-foot-high wall of foam made it hard to gasp actual air. “I thought I was going to die,” says Cain, who credits his survival to pure luck—despite unlucky gambling in the slots. “In canyons like Spry,” says Cain, “a one-in-three chance of rain might mean drowning.” $5 permit required
The Danger: Snowfields
Mt. Dickerman Trail, Mt. Baker-Snoqualmie National Forest, WA
Cherry-picker views of volcanic hulks Mts. Baker, Glacier, and Rainier await atop 5,723-foot Mt. Dickerman. But the 4.3-mile route crosses steep, exposed hillsides pocked with snowfields that linger well into summer (bring crampons and an ice axe).
The Danger: Glaciers
Emmons Glacier, Mount Rainier NP, WA
In the Lower 48, little compares to the satisfaction of summiting Rainier, the most glaciated peak in the contiguous U.S. But its crevasses make the descent risky—especially in May and June, when cracks are harder to detect than in late summer.
The Danger: Steep Snow
Conundrum Couloir, Maroon Bells-Snowmass Wilderness, CO
Fifty-degree pitches and an overhanging cornice spice up this classic snow climb. Hikers who fall will slide and bounce like pinballs to its base.
The Danger: Narrow Ledges
Precipice Trail, Arcadia National Park, ME
This 1.6 mile climb of Champlain Mountain packs trance-inducing Bar Harbor views—after climbing iron handholds and stepladders, traversing lengthy unmarked rock fields, and braving dizzying drops along a two-foot-wide ledge.
The Danger: Mud and Disappearing Paths
Florida Trail, Big Cypress NP, FL
These 30 swampy miles slosh through knee-deep water and oozing mud that challenge routefinding experts and make a GPS essential. But primal pleasures include sighting gators, scarlet bromeliads, and graceful egrets.