What she'd wanted was to hike for a year—a whole year on the trail, sleeping in a tent, walking across the country. When the idea first struck Heather Anderson to hike the three major national scenic trails, the Appalachian, Pacific Crest and Continental Divide trails, in a single calendar year, part of the allure was that it would take most of the months of that year. That was how long it had taken Brian Robinson when he became the first person ever to acompliance that feat in 2001. Seventeen years later, in Grants, New Mexico, Anderson became the first woman to achieve that goal, hiking more than 7,000 miles in just over eight months.

Anderson, known among the thru-hiking community by her trail name, "Anish," has logged more than 20,000 miles on trails, including hiking all three major national scenic trails, the so-called triple crown of hiking, twice already since her first AT thru-hike in 2003. She set speed records on the Pacific Crest (PCT) and Appalachian (AT) trails in 2013 and 2015, finishing them in 60 days, 17 hours and 12 minutes and 54 days, 7 hours, and 48 minutes, respectively. Most people take six months for those hikes, not two. She works now as a personal trainer, coaching other people toward their own hiking goals, and has written a book about her PCT record-setting hike called Thirst: 2,600 Miles to Home, that's due out in March.

But completing the triple crown in a calendar year hovered in the back of her mind.

"I definitely know better than to be like, 'What will I do to top the things that I've done?' but 'What are the unfinished dreams I have from the past?'" she says. "This came to mind. That was my first big dream."

She chose this year for her attempt to align with the 50th anniversary of the National Trails System Act, the legislation enabling hikers to piece together walking paths that bisect the nation.

People usually start these trails from their southern ends and hike north with the spring, but Anderson needed more time than that. So she started the AT in March, hiking through drifts of snow as winter lingered. The corridor of Virginia often called "the green tunnel" she found leafless and its views expansive. Instead of the sweltering heat and humidity she'd previously experienced on that trail, she was met with freezing temperatures. Where crowds often pack the path, she passed whole days with the trail to herself.

After reaching New Hampshire and the forbidding White Mountains in May, she flew to Albuquerque and took a bus to Grants. The destination was selected as much for its ease of access from the airport as anything, she says, but it set her eventual finish line. For nine days, she walked the Continental Divide Trail, where it winds past the lava fields of El Malpais and into the Gila National Forest, camping amid ponderosa pines and hiking in the sunshine. New Mexico marks the southern portion of a trail that then follows the spine of the continent through Colorado, Wyoming, Idaho, and Montana.

"They say that the rainbow is God's promise not to flood the Earth again," she wrote on Instagram as she hiked through the desert in May. "I think that a river flowing through the desert is a far more tangible promise. One that I can lie down in with nothing but my face above the surface and smooth stones pressing into my back."

Once she'd reached the southern end of that trail, she moved to California's starting line for the Pacific Crest Trail. Unlike the others, which she'd piece together, these 2,600 miles she walked straight through—and with company. Her fiancé is still working on his first triple crown and she wanted to walk this one with him. That trail starts in southern California's desert before climbing into the high Sierras, then to Oregon and Washington.

She started the CDT south from Montana, trying to beat winter as it moved into the Rocky Mountains, then leaving briefly to finish the AT, before picking back up in Southern Colorado on the CDT. Her last trail miles were from the Colorado border south to I-40.

She completed the triple crown for the first time from 2003 to 2006, and then for a second time from 2013 to 2017. This year, she walked them in new seasons and new ways, revisiting paths that had shaped and directed who she'd become and says what struck her was how she could now see past their obvious differences to the similarities among them all.

In some ways, her sort of randomly selected finishing points are a little strange, she says, "and in other ways, I found that to be really refreshing and meaningful in a different way. I feel like we put a lot of focus in our lives on destinations, whether it's getting the perfect picture or having the perfect finish location, like finishing on [the AT's northernmost point, Mount] Katahdin, and focusing on the end instead of the journey. Having very arbitrary finishes and a very arbitrary finish to this whole thing makes it less about getting to a specific spot and more just about the process."