Last September, as the season’s first snow was beginning to coat Denver, I went down to my basement to start pulling out my winter layers. I had packed away the heavy-duty stuff in a Rubbermaid tub, buried underneath boxes of books and holiday decorations. As soon as I opened the box, the scent hit me in the face.
It smelled like wood smoke, not a hint, but a thick, heavy wave of it. A little digging revealed the layer responsible, a blue down Cotopaxi Fuego puffy. I had last worn it almost a year earlier, on a late-season Editors’ Choice trip to Bears Ears National Monument in Utah. As I held it in my hands, sensations from the trip flooded back to me: The lengthening shadows as the sun dipped behind the canyon walls; the way the chill suddenly blanketed our campsite at dusk; the vegetal smell of algae-lined watering holes; the feeling of loose sand shifting beneath my feet as our group hiked up an arroyo. The memories were almost immersive.
Like most other backpackers, I take a lot of photos. But a photo is always going to be a flat recollection—a window to the world, not a door. A good souvenir does something that a photo can’t, awakening memories linked to our other four senses. The feel of warm sandstone against the skin or the taste of a roasted marshmallow can transport you back to a place so viscerally that it almost seems like you’re there again. It’s why people still pick flowers and take rocks at national parks even after decades of being told not to. My smoke-scented jacket was a more Leave No Trace-friendly version of that: a bit of somewhere magnificent that I got to put in my pack and carry home.
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When I remember places I’ve hiked, it’s often the smells that come back first. The high desert in New Mexico was herby sagebrush and the rotting-fruit scent of blooming chamisa to me; the midwestern oak forests where I grew up were wet leaves and humus. But the scent that takes me back most intensely is that charred campfire smell, baked in during hours spent with friends around a fire pit.
It’s not just me, either: The human nervous system is wired to build powerful memories around familiar scents. As Venkatesh Murthy, chair of the Department of Molecular and Cellular Biology at Harvard University, explained it to the Harvard Gazette it, a part of the brain called the olfactory bulb is responsible for processing smells we encounter; it sends information on them directly to the amygdala and hippocampus, two areas of the brain with strong links to emotion and memory. Like much of neuroscience, our understanding of the way our brain handles scent is still in its infancy, but evidence suggests that what we smell may be responsible for creating more powerful memories than what we see.
Thanks to fire restrictions and general laziness, I don’t often have campfires when I backpack. But when I do, I tend to come home smelling like them. Part of that is because I run cold and huddle as close to the fire as I can when one’s available. Part of it is my near-mystical ability to attract campfire smoke; whenever I sit down, I swear the wind changes direction to blow it directly in my face (science has been unable to explain this thus far.) Part of it is undoubtedly the way that synthetics hold onto scents. In the moment, my brain seems to relegate this smell to the background or filter it out; I never notice it until I’m home and showered. After that, it’s all I can smell.
I know my smoky souvenir won’t last forever. I’ve used that jacket on ski tours in Colorado and a backpacking trip in western Nebraska since then; eventually, I’ll have to wash out the sweat and dirt, and the smoke along with it. Until then, every time I put it on, I’ll take a trip back to somewhere far away, where a fire is crackling, the sand is bleeding off the day’s heat beneath my feet, and sandstone towers loom against the starry sky.