If locals say “Go high or go home” is this park’s unofficial motto, then this 25.2-mile tundra-topped loop is its poster child. Park at the Tonahutu/North Inlet trailhead on RMNP’s less-trafficked west side, and go north on the Tonahutu Trail. Hike along lodgepole pine-lined trail to the junction with the Tonahutu Spur Trail at .8 mile.

Ramble beside Tonahutu Creek to where the forest thins at mile 3.2. Big Meadows, a two-mile-long field flanked by spruce and filled with a dozen varieties of wildflowers (bloom starts in July) stays hidden until after the junction with the Green Mountain Trail. In 1.7 miles, pass Sunset campsite, and, permit willing, continue 3.6 miles past seven more campsites and 30-foot Granite Falls, to Hynach llama camp, via a .4-mile hike on the Hynach Lakes Trail. Located at 10,707 feet in a pine-bottomed valley, this campsite offers a surround-sound wilderness experience—a rushing stream, yipping coyotes, and bugling elk.

Return to the Tonahutu Trail junction early the next morning (by 7 a.m.) to avoid summer’s afternoon thunderstorms on the exposed alpine miles ahead, and ascend across granite talus to Bighorn Flats. Mountain views open to the west on this treeless slope. Climb toward Ptarmigan Point (12,363 feet) on the Continental Divide. At the Flattop Mountain Trail junction, drop your pack and hike to the rock-lined rim at Flattop’s 12,324-foot summit above Emerald Lake. The trail continues south past knee-high cairns with eastern views of 14,259-foot Longs Peak.

At mile 15.7, descend 1,400 feet in 1.3 miles on switchbacks to Hallett Creek. Continue down with occasional views of 12,324-foot Ptarmigan Mountain. After North Inlet Junction campsite, there’s a second string of camps. Aim for the dispersed zone south of 60-foot Cascade Falls. The next day, knock off the final three miles between high and home.

INFO For information on permits, current trail and camp conditions, and wilderness guidelines, go to nps.gov/romo/planyourvisit/backcountry.htm

PERMIT A wilderness permit is required for all overnight camping in the backcountry. Reservations accepted ($20 administrative fee for permits during peak season). nps.gov/romo/planyourvisit/backcntry_guide.htm

CONTACT Rocky Mountain National Park, (970) 586-1206; nps.gov/romo

GEAR UP: Rent bear canisters (required, $5/day) at Never Summer Mountain Products. 919 Grand Lake Ave., Grand Lake. (970) 627-3642.

-Mapped by Casey Lyons

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