New Hampshire has a crack in the earth 90 feet deep — and you walk right through it

It’s 200 million years in the making

At the base of Mount Liberty in Lincoln, New Hampshire, a crack in the earth runs 800 feet long and barely 12 feet wide in places.

Granite walls rise 70 to 90 feet on both sides, and a wooden boardwalk carries you right through the middle of it, just above the brook that carved everything you see.

Flume Gorge sits inside Franconia Notch State Park, between the Kinsman and Franconia mountain ranges. The geology here starts in the Jurassic Period, and the walk takes about an hour and a half.

Basalt wore away and left the canyon behind

The granite beneath your feet cooled from molten rock about 200 million years ago, deep underground. As it hardened, it cracked, and basalt pushed up into those fractures.

Over time, the softer basalt eroded faster than the harder Conway granite around it, and a canyon opened up. Glaciers rolled through during the Ice Age but barely touched the gorge.

When the ice melted, Flume Brook picked up where it left off and keeps cutting deeper today.

A 93-year-old woman found it while fishing

In 1808, a woman named “Aunt” Jess Guernsey stumbled onto the gorge while out fishing. She was 93 years old.

Back then, a massive egg-shaped boulder hung wedged between the two walls, about 10 feet high and 12 feet long. For decades, people came just to see that rock suspended in midair.

Then in June 1883, a violent rainstorm triggered a landslide that knocked the boulder loose. Nobody has found it since.

The 1883 storm carved a 45-foot waterfall

That same storm didn’t just sweep away the boulder. It deepened the gorge and created Avalanche Falls, a 45-foot drop at the upper end of the canyon.

Flume Brook spills over a cliff edge and crashes straight down into the rock below. You can walk the boardwalk right up to it, close enough that the spray hits your face and coats the railing.

It’s one of the most photographed spots on the whole trail.

The boardwalk hangs above the brook

The full loop runs about two miles on packed gravel and wooden boardwalk with some moderate uphill stretches and stairs. Inside the gorge, the boardwalk clings to the granite walls just above Flume Brook.

Moss, ferns and small wildflowers push out of every crack in the rock on both sides.

The shade and the mist from the water drop the temperature a few degrees, and sound bounces off the walls in a way that makes the brook louder than you’d expect.

Cross one of New Hampshire’s oldest covered bridges

Before you reach the gorge, you’ll cross the Flume Covered Bridge, a red wooden span dating to 1886. It sits over the Pemigewasset River near the start of the trail.

“Pemigewasset” comes from an Abenaki word meaning “swift or rapid current,” and the river earns the name.

The bridge has gone through several restorations over the years, but it still looks like something from a different century, especially in October when the foliage lights up around it.

Table Rock gives you a preview of the geology

Along Flume Brook, before the gorge narrows, you’ll walk past Table Rock.

It’s a stretch of Conway granite, about 500 feet long and 75 feet wide, worn flat and smooth by the rushing water. The exposed rock face is your first real look at what shaped everything ahead.

Trail signs explain the formations and natural history along the way, so you start to read the landscape before you even step between the walls.

A 175-foot pine tree holds up a bridge

The Pool is a deep basin in the Pemigewasset River, roughly 40 feet deep and 150 feet across, ringed by cliffs that rise 130 feet. It formed at the end of the Ice Age, about 14,000 years ago.

Above it stands the Sentinel Pine Bridge, a covered bridge built in 1939 on top of a massive pine tree that the hurricane of September 1938 ripped out of the ground.

That tree measured nearly 175 feet tall, and the bridge builders used it as their foundation.

Liberty Gorge is the quieter second act

After you leave the main gorge, the trail drops into Liberty Gorge, a smaller canyon with a mountain stream cascading through it. The water flows down through the narrow valley and joins the Pemigewasset River below.

A viewing platform lets you look straight down at the cascade from above.

Fewer people linger here compared to the main gorge, so you get a moment to stand still and listen to the water without a crowd at your shoulder.

Crawl through the Wolf Den on your hands and knees

Just past Avalanche Falls, Bear Cave waits. It’s a shallow, lit cave formed by a cluster of boulders, and kids can walk right inside.

A little further along, the Wolf Den narrows to a one-way path where you crawl on your hands and knees through the rocks. If tight spaces don’t bother you, it’s a good time.

Both spots break up the trail and give the walk a sense of exploration that goes beyond the main gorge.

300-ton boulders the glacier left behind

Scattered through the forest along the trail, massive rocks sit where a mile-thick ice sheet dropped them more than 25,000 years ago. Some of these glacial erratics weigh over 300 tons.

As the glacier retreated, it left them behind like loose change.

You walk right past them on the path, and the scale hits you when you realize that nothing short of a continental ice sheet could have moved them here.

Two covered bridges and three waterfalls in two miles

Flume Gorge packs 200 million years of geology into a single afternoon.

Jurassic-era granite, Ice Age pools, a 19th-century storm that reshaped the canyon, two covered bridges, three waterfalls, caves and glacial boulders all line this two-mile path.

The trail works for most ages and fitness levels, and you can take it at your own pace. Few places in the White Mountains give you this much ground to cover in so little distance.

Walk the boardwalks at Flume Gorge in New Hampshire

You’ll find Flume Gorge inside Franconia Notch State Park at 852 Daniel Webster Highway in Lincoln, New Hampshire. The boardwalks go up in May and come down in October.

If you book online, admission runs $18 for adults and $16 for kids ages 6 to 12. Walk-up tickets cost $3 more per person, and children 5 and under get in free.

Grab a timed-entry reservation early, because popular slots sell out. Leave pets at home.

The visitor center has restrooms, food and a 20-minute film about the park.

This article was created with AI assistance and human editing.

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