Exploring a gorge, which is similar to a canyon, only not nearly as wide, is not for the claustrophobic traveler, especially when it comes to Flume Gorge, the geological wonder that draws visitors to its location inside Franconia Notch State Park in New Hampshire's White Mountains. At its most narrow point, the gorge is just 12 feet wide, while its granite walls reach 90 feet high. So it's a tight space tucked inside a steep crevice.

However, most of Flume Gorge's 800-foot length is considerably wider than 12 feet, and its wooden boardwalks and stairways escort visitors past its moss-covered sides, its waterfalls and ponds, and its boulders that make fun of hiding places for children.

Franconia Notch State Park sits within the White Mountain National Forest, almost smack in the middle of New Hampshire. The notch refers to a mountain pass that links the Franconia and Kinsman mountain ranges.

The formation of Flume Gorge and others in the area happened millions of years ago, during the Jurassic Period, and there are detailed scientific reasons as to how and why. In a simplified explanation: The cooling of molten rock deep beneath the earth's surface caused the rock to fracture, and with erosion over time, the fractures eventually became filled with water, creating the gorge and its multitude of waterfalls.

Flume Gorge and the nearby Lost River Gorge & Boulder Caves are the most celebrated gorges in the region. A third, the Chesterfield Gorge Natural Area, is much smaller and less impressive since it lacks the tall granite walls found in the other two.

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Visitors Can Stroll The Boardwalks Through Two Gorges

Tourists who enter Flume Gorge should be prepared to navigate narrow ledges, walk up and down staircases, and walk along boardwalks, all of which can be slippery due to the extremely moist atmosphere inside the gorge. But the trip is well worth it since the geology of the gorge is fascinating to contemplate. Although the gorge is estimated at 200 million years old, it wasn't discovered until 1808, when a fisherman stumbled into it.

It's slow going through the gorge and will take a visitor about 1.5 hours to traverse the whole trail, which is a two-mile loop. Along the trail, explorers also will see the Flume Covered Bridge, built in 1886; Table Rock, which is an outcropping of rock some 75 feet wide; and Avalanche Falls, a 43-foot-tall waterfall at the top of the flume.

Advance reservations are encouraged at Flume Gorge since walk-in tickets are limited. Adult admission is $18 online and $21 at the ticket window. There's a $4 admission to enter the state park as well. Enter the park at 852 Daniel Webster Highway in Lincoln.

For visitors who'd like to make a day of it, there are other things to do in the park, such as riding the Franconia Notch Bike Path. Bike rentals are available in the park. In the summer months, the park operates the Cannon Mountain Aerial Tramway, which brings visitors to the summit of Cannon Mountain (elevation 4,000 feet), where they'll see views of the mountain ranges in New Hampshire and beyond. There are walking paths at the summit.

Lost River Gorge & Boulder Caves is at Kinsman Notch, roughly 10 miles from Flume Gorge. It is another of New Hampshire's natural wonders, and like Flume Gorge, it's a self-guided tour along a one-mile boardwalk bordered by several boulder caves and waterfalls. The best views are from a viewing platform called the Giant Bird's Nest and from a suspension bridge in the upper regions of the gorge.

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The gorge, located at 1712 Lost River Road, Woodstock, was named for a brook in Kinsman Notch that disappears below the surface in the gorge. And like Flume Gorge, it has a lot of stairs – about 1,000, so good footwear is recommended. Adult admission is $22 online and $26 at the ticket window. Advance reservations are suggested.

Plenty Of Lodging Choices In The White Mountains Region

Tourists looking for overnight accommodations or a multiple-day getaway have a wide range of options across the White Mountains area, from luxury properties to budget motels. Rates will be highest during summer, fall foliage season, and ski season.

The Omni Mount Washington Resort in Bretton Woods is a high-end hotel with a range of suites, a full spa, two pools, multiple restaurants, and other amenities. Summer, fall, and ski season rates can reach or exceed $900 per night, dropping by half at other times of the year.

The Eastern Slope Inn Resort in North Conway offers rates in the $250 to $350 range in the busy seasons, then drop to around $200 in off-season months.

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Indian Head, located in Lincoln and featuring rooms, cottages, and bungalows, will cost from about $170 during fall foliage season, while Carlson's Lodge, a smaller, family-owned hotel in Twin Mountain, has summer and fall rates starting at about $140.