The rugged chaparral of California’s Sespe Wilderness lay hidden under the camouflage of mahogany and sage hues. Nearly a week into her thru-hike on the Condor Trail, Brittany Nielsen surveyed this scraggly landscape. She had already faced a downpour, severe flooding, and hypothermia. Now, she leaned against her pack in the spring sun, scanning the thickets and hoping the trail would emerge like a scrub jay.

“I learned a lesson about being calm while being lost on the trail,” Nielsen says. Earlier, behind on miles and low on her food supply, she had searched for the path in a frenzy, only to find herself exhausted. The trail on the side of Sespe Creek was fiercely overgrown in sections and required strong orienteering skills to navigate.

“When I opened my eyes I was looking at the sky,” Nielsen says, “And up above me—I couldn’t believe it—there was a condor.” She noted the telltale band of white feathers in the shape of a scalene triangle that decorated the bird’s nine-foot wingspan. When the condor drifted out of sight, Nielsen dropped her gaze into the chaparral where, directly in front of her, she discovered a small rock cairn that marked the trail.

Over the course of her 37 days on the hike, Nielsen would lose and gain the trail numerous times as she fought through menacing brush and screamed expletives that no one could hear in the most remote pockets of Los Padres National Forest. She would travel through seven wilderness areas, along the shores of central California, past colonies of elephant seals, and across the ancestral lands of the Chumash, Salinan, Esselen, Tataviam, and Costanoan peoples.

SOURCES: BRYAN CONANT; IUCN REDLIST

Unlike California’s well-established John Muir and Pacific Crest Trails, the Condor Trail is a thru-hiking “route,” meaning its course exists—as a continuous thread of trails and roads and cross-country travel—but that it lacks proper signage and maintenance. While these popular thru-hiking routes receive hundreds of hikers a year, Nielsen took on the Condor Trail alone in 2015. When she finished on June 18th, she was the first thru-hiker to complete it.