That night, on the outskirts of camp, the woman collapses inside her tent and still she can't sleep. Haunted by his ghost and strangled by the memories she can't put down.

The next morning she rises early and starts packing up her tent.

Where are you going? The elder had seen her from camp and walked over to talk to her. There's more caribou to hunt.

She peers out at the horizon. Then back to him. I forgot something down south that I shouldn't have left.

He looks puzzled but nods slowly. So you finally found him.

She smiles and gazes out across the Brooks Range. A slight breeze is up, blowing south across the tundra. The gusts keep the bugs down but bring the first hint of winter.

After breakfast the woman sets out across the tussocks, spongy muskeg bouncing underfoot like giant moss-covered pillows. Bear flowers and arctic lupine sway at her side. After another four days she'll cross the Brooks Range. But for now, she thinks of him, hoping she can find the man when she gets back to Colorado.

This trip she wastes no time exploring new routes. The woman retraces her steps, following that nameless river, up the wide, snaking drainage toward the top of the pass. As she crosses over to the south side of the Brooks Range, and begins her descent, she notices the first trees she's seen in weeks. Sparse and stunted at first, the spruce stands thicken as she drops to lower elevations farther south.

Back at the road where months ago the prospector dropped her off, she walks a few miles before she hears gravel popping and crunching behind her, turns, and sticks her thumb out for an old green pickup already slowing down. An Athabascan man who prefers silence takes her all the way to Fairbanks, speaking only occasionally to offer her a smoke, point out memorable fishing holes or hunting grounds. A smooth bend in the Koyukuk, stretching into mist and heavy timber. A lichen-covered plain north of Finger Mountain.

By the time she nears the border, the first reds and yellows are draining from the tops of aspens. A few rides later, the woman crosses into Canada where she'll zigzag the Divide for hundreds of miles. Down half the continent. Glaciers spilling from high mountain bowls. Jagged pinnacles of rock spiraling up through ancient ice fields.

She runs mostly on adrenaline, never stopping unless she's out of food. And then only briefly. Like the pass she summits in the Sawtooth Mountains. Dropping into a deep, narrow drainage, she fishes for trout in a stream that splits two mountain slopes ablaze with fall colors. Oranges and purples so vivid they practically drip with color.

After eating her fill, she follows the creek that grows, mile after mile, into a stream. Further down, rocky canyon walls squeeze the river into a cascade of foaming white water and from a nearby granite rim she watches a series of falls—broken by boulders—forcing the braids of that torrent to crash together and spray foam in ever-changing patterns.