Permian Reef Trail

Permian Reef Trail is a strenuous out-and-back from McKittrick Canyon Trailhead to the Texas–New Mexico boundary gate: 4.8 miles one way, 9.6 miles round trip. Allow five to seven hours. The route climbs from McKittrick Canyon to Wilderness Ridge, then follows a rockier, more wooded crest to the gate at the park boundary. There's a hard uphill, fossil stops and broad views into South McKittrick Canyon. I'd choose it if geology matters as much to you as a summit view. Expect about 2,000 feet of rise on the main climb, with extra ups and downs along the ridge; it's a full-day hike, not a quick canyon walk. A separate 0.3-mile Geology Loop near the start gives you a much shorter look at the rocks.

Several trails start at McKittrick Canyon Trailhead by the ranger station. Follow the Permian Reef sign to the right as you leave the station. The route briefly follows a gravel road and a wash before a narrow trail splits to the right; the low marker at that turn is easy to miss. Around 0.4 mile in, bear left at the signed junction to stay on the main trail. The optional Geology Loop branches and rejoins nearby. If you want help reading the numbered stops, the Texas Bureau of Economic Geology's trail guide is sold at Pine Springs Visitor Center, a separate stop before the drive to McKittrick Canyon.

The first stretch is rough and rocky, with cacti, a cliff face, a pillar-like outcrop and a small cleft in the rock. The climb eases in places but keeps gaining height. Canyon views gradually open as you rise. After a ridge crossing, look east; farther on, a notch in the rock frames a view back into McKittrick Canyon. Most of the ascent faces south and stays in the sun, so don't let the lower wash's shade fool you about the heat higher up.

The long climb gives way to a more level, rocky walk among trees and shrubs on Wilderness Ridge. It's still uneven, and the trail zigzags near the ridge edge. Several openings look down into South McKittrick Canyon, so pause at the successive viewpoints rather than expecting one single lookout. Numbered geology markers run up to 28 near the high country. Follow the main tread to the boundary gate. The trail continues into Lincoln National Forest beyond it, but that extension is outside this park route and isn't part of the 9.6-mile round trip here.

The pale cliff above the canyon is the Capitan Reef, a mass of Permian-age limestone built from marine life along the edge of an ancient sea about 299 to 252 million years ago. The trail's markers point out fossils and different rock deposits, making the long climb a geology lesson as well as a walk to the ridge. Look closely at the rock underfoot: the patterns are the remains of a reef, not random marks in ordinary limestone. The trail guide makes the numbered stops much easier to follow.

The National Park Service recommends winter, spring and fall for this exposed south-facing route. Carry enough food and water for a strenuous 9.6-mile day; no drinking-water source on the route was confirmed. McKittrick Canyon is day-use access, so plan to be back through the entrance gate before it closes. Overnight parking and camping at Wilderness Ridge require a Wilderness Use Permit. Pets aren't allowed on park trails except trained service animals.