Lexington Arch is a rare, 75-foot high limestone arch located in a canyon at the southeastern edge of the Great Basin National Park.
How did it form?
Rising high above the floor of Lexington Canyon, this imposing natural arch was created by the forces of weather working slowly over a span of centuries. Lexington Arch is unusual in one important respect: it is carved from limestone. Most of the natural arches of the western United States are composed of sandstone. The fact that Lexington Arch is made of limestone leads to speculation that it was once a passage in a cave system. Flowstone, a smooth glossy deposit that forms in caves has been found at the base of the opening, lending support to this theory.
It is even possible that Lexington Arch is actually a natural bridge. The distinction: an arch is formed by the forces of weathering, such as ice, wind, and chemical breakdown of the rock. A natural bridge, by contrast, is formed by the flowing waters of a stream. It is possible that long ago when Lexington Canyon was less deep, the waters of Lexington Creek flowed through a cave in the wall of the canyon, in the process enlarging the tunnel that later became Lexington Arch. If this happened then the Arch is truly a natural bridge.
Whatever the case may be, the forces of weather continue to sculpt the Arch. The limestone is particularly vulnerable to the dissolving action of rainwater. As time goes on the rain, ice, heat, and cold chisel the Arch into a unique natural form that will continue to change with the passage of centuries.
Planning your trip
Lexington Arch is located in a remote and wild section of Great Basin National Park. The dirt road is unimproved. Be prepared for rugged terrain and remember the high elevation. Hiking boots are essential on the rough rocky trail. Bring water and a snack and be prepared to spend the better part of a day driving and walking to Lexington Arch. Weather conditions can change rapidly, so come prepared for all types of weather, including sudden rainstorms and snow.
The road to Lexington Arch is currently open. It is an unimproved dirt road that is rough and rutted. High clearance 4-wheel drive vehicles are required. Advanced 4-wheel driving skills required to reach the trailhead. Route finding is necessary at parts of the trail due to flood damage.
From the Great Basin Visitor Center in Baker, drive south on NV Hwy 487 10.7 miles (17.2 km). On this stretch you will cross the state line into Utah, at which point NV Hwy 487 becomes Utah 21. Pass through the town of Garrison, and then pass Pruess Lake on your right. Look for the first dirt road on the right just south of Pruess Lake. Turn right onto the dirt road with a sign for Lexington Arch.
Proceed west 12.0 miles (19.3 km). The road will branch in a few places. At each fork look for the sign indicating the correct direction to Lexington Arch. The road ends in a small parking area with a sign indicating the trail to Lexington Arch. Park here.
The hike to the base of the Arch is 1.7 miles (2.7 km). The trail rises 820 feet (250 m). The first mile of the trail climbs up a steady grade and then levels off before crossing into the park. The last quarter mile climbs several short switchbacks to the arch.
Great Basin National Park is home to Lexington Arch, one of the largest limestone arches in the western United States. This six-story arch was created by the forces of weather working slowly over the span of centuries. This type of above ground limestone arch is rare.
For more information visit http://www.nps.gov/grba/planyourvisit/lexington-arch.htm