If you were at Burning Man in 2025 and found yourself deep playa bound, there's a good chance you encountered the Sphinx Gate, two colossal, 34-foot, white figures rising from the dust, seemingly sentient, watching everything below with a patient, inscrutable gaze. If you missed it, maybe you caught it on HBO's docuseries “The Man Will Burn,” or came across it in a late-night Instagram rabbit hole instead. 

The installation was impossible to ignore. By the end of the week, word had spread to all four quadrants of Black Rock City. Thousands crossed the threshold, passed between the two Sphinxes, and many came out changed. One woman walked in torn about leaving the career she'd built, and walked out, having made a decision that would change the shape of her life.  Each participant was invited to, as the Gate's own materials put it, "Know thyself.” 

One person behind it was founding artist Mareesa Stertz, a storyteller, filmmaker, one of DoubleBlind's Influential Women in Psychedelics, and is a co-founder of both the Global Psychedelic Society and Lucid News. Her work includes documentary film, community-building, immersive art, and storytelling workshops about personal growth. Across all of it, Stertz returns to the same question: "What might change if we made inner work more accessible, communal, and even fun?" 

Sphinx Gate was how she took that question out of her head and into something people could walk through and answer for themselves. The project began in 2019 and debuted at Burning Man in 2025, backed by that year's largest honorarium grant. Co-lead Tania Abdul, architect Jason Chase, 3D designer Goose Manriquez, and experience designer Melanie Pincus brought it to life with steel, cloth, and foam, alongside nearly one hundred volunteers. It grew from a conviction Stertz keeps returning to: "The way we talk about mental health implies people are broken and need fixing. Of course they avoid it. It's not that people don't want to feel better. It's that we've made this sound like something you only do when something's deeply wrong." 

What she suggests instead is a framework she's developed called "inner hygiene". We traditionally look after our bodies, homes, and diets, but so often neglect our thoughts and feelings. Tending to the inner parts of ourselves, she believes, could become just as ordinary as anything else we do to take care of ourselves. 

This year, anyone who may have come back for the Sphinxes found no structures at all, but instead something much more distilled, yet just as impactful: Know Thyself, an immersive ninety-minute ritual of movement, sound, and reflection, named for the original inscription, which carried the full weight of the journey without the steel or structures.

Know Thyself travels on this fall, with scheduled performances in Lisbon, Berlin, and more of Europe, with hopes of returning to the playa in 2027. Stertz is looking for collaborators, funders, and hosts to bring the experience into public space.

We sat down with Stertz to talk about how the Sphinxes came to be and what they represent, as well as where the concept of “inner hygiene” came from, how she translated the psychedelic hero's journey into something you can experience drug-free, and why tending to our inner worlds might be one of the most radical things we can do right now. 

*This interview has been edited for length and clarity

Mareesa Stertz: I’ll start with a question to you. Is there a thought you have that keeps you feeling stuck in life? A reaction or behavior you repeat that you can’t explain?

Most of us have something inside us that keeps showing up, and we don’t know how to deal with it. We brush our teeth, watch what we eat, clean our homes; but we don’t do the same for our inner world. Why do we wait for depression, anxiety, or to hit rock bottom before we pay attention to what’s going on inside? 

All of it points to a bigger collective blind spot: that this isn’t easy to talk about or work on. There’s a lot of shame involved. Inner hygiene is my attempt at building that literacy. It is the regular practice of tending your inner world, processing your experience as it comes and really feeling it rather than avoiding or disconnecting.

There are countless ways to do this. Somatic work, psychedelics, self-compassion, narrative work, breathwork. Sphinx Gate is my version, stripped down so a stranger can do it in fifteen minutes on their own. But the term is bigger than what we built, and I hope other people use it for what they build.

I grew up with terrible inner hygiene. I was told not to be so sensitive. Don’t be a baby. So I learned to hide my feelings, distract, and avoid. As an adult, I numbed with alcohol and overworked until exhaustion, often feeling broken, confused, and desperate, with no idea what to do about it.

It was rediscovering psychedelics in community that finally gave me a way forward, but it was messy. Some journeys helped, others left me more confused about what had happened or what to do. After several frustrating stops and starts, I realized we needed a map.

And then a few meaningful psychedelic journeys lit another fire under me: The world needs to know! And I can help! I felt like I was on a quest, not just to make sense of what had kept me stuck for so long, but to figure out how to make the path easier for others to find. 

I documented everything: journaling, filming, running storytelling workshops, assisting at retreats, and helping people tell their psychedelic stories. Across all of it, I kept seeing the same arc: people would encounter something difficult within, stay with it instead of running from it, and come out the other side with a different relationship to themselves.

The more I saw that pattern, the more I wondered: was the medicine only one way of getting there? Could this process be made more accessible? Could people learn to move through it without the medicine?

That’s when the words inner hygiene landed. The World Health Organization defines hygiene as the conditions and practices that help maintain health and prevent disease. We’re talking about upkeep. The same way we tend to our bodies, we can tend to our experiences and how we process them.

It’s a word even a skeptic or a clinician can get on board with. Plus, nobody flinches at hygiene the way they do at healing or trauma work. I’m just looking for a language entry point the mainstream can use, so this work reaches people who don’t know how to look for it. Like the younger version of me.

MS: There are three ways to encounter it: the two 34-foot sculptures that went to Burning Man, the six-foot Sphinx Portals that travel to festivals, and Know Thyself, the live ritual where I take a whole room through the journey together. Same journey, same tags, no sculptures in the ritual. The whole thing fits in a bag.

It always opens with an invitation: Welcome, Seeker, you're on a quest. You will be challenged. It will be hard. But that's okay, because that's how we grow. Do you feel brave? Then some breathing, grounding, and a check-in on whether you’re resourced enough to go in.

You begin the journey through four portals, each one asking you to meet a different part of yourself.

The first portal is Mind. On a tag, write down the riddle of your mind, the hard thought keeping you stuck. Usually it's some version of you're too much, you don't belong, you're not enough, or there aren't enough resources.

The second is Body. Find where that thought lives in you. The tightening in your chest. The sinking in your gut. Let yourself feel it, then let it move through you. Shake it, stomp it, dance it out.

The third is Heart. Bring acceptance and compassion to it. Feel the uncomfortable feelings, not to fix them but just to be with them. 

The fourth is Destiny. The only constant in life is change, so ask what's on the other side of this challenge, and write the new story you want to step into on the back of your tag. 

Then, you honor your experiences by crossing the threshold between the sphinxes while being witnessed by the community. At the Burn, there was a platform people walked up to for their moment of being seen, and inside one of the sphinxes, an oracle would greet you and send you out with a mission.

The last step is the web of community wisdom, where everyone hangs up the riddle of their mind and the story they're claiming. That's the part people don't see coming, and it was one of my favorite things to watch. You go in thinking you're the only one struggling with your issue, and you come out reading tag after tag with the same struggle, just a different version. “I truly feel like I don't belong anywhere.” “I'm a disappointment.” “I feel silly dancing.” It turns out we're all grappling with the same handful of problems.

MS: Around the time I was building Sphinx Gate, I was running storytelling workshops, and my students kept surfacing the same pattern I was finding in my journeys. It’s the hero’s journey, but not the tired version, where somebody becomes great and rises above everyone else. Read through the lens of Jung’s individuation, it’s a map of how we reclaim the parts of ourselves we’ve lost or disowned and become conscious of what’s operating outside our awareness. You inherit a belief from your environment that disconnects you from yourself, something like “I’m not wanted.” Then you find evidence of it, or recreate it everywhere you go, until it builds into something so big that you find yourself in the abyss. That’s where you discover you’re strong enough to survive it, and that the story you’ve been living in may not even be true.

A 2024 paper from Ari Brouwer, the Erowids, and Robin Carhart-Harris found that same arc in mushroom experiences. Psychedelics take us into the hardest part of the experience, and it’s by staying with it rather than escaping that it resolves.

Gabor Maté describes trauma the same way, as an experience that never finished processing and got stuck in the system. The four portals are that same arc without the medicine, in an order a stranger can follow. 

The more I wondered how to make it accessible without medicine, the more I saw this pattern in everyone. Psychedelics hadn't created it, they'd just made me aware of it. 

Though I designed this as a sober parallel to a psychedelic journey, psychedelics were part of the experience for plenty of people, especially at Burning Man. One person came through after a challenging night on mushrooms and said walking the portals helped him integrate what had happened. Others explored it while on MDMA and described the experience as deeply therapeutic.

MS: We spent a lot of time thinking about how to make the experience feel accessible and supported. Whether it's at a festival or in a public square, we're inviting people to look at some pretty deep stuff, and wanted to make sure it held people well.

That starts at the entrance, where you're told you're in charge: you can walk away at any point, go only as deep as you want to, and give yourself permission not to have the answer.

We playtested the experience through multiple rounds before trusting it was ready for the public. But we also knew some people would be moving through it on psychedelics at Burning Man, so we staffed it from 9 p.m. to 3 a.m. every night with stewards, volunteers trained to support Seekers who needed extra help. 

Our biggest inspiration was the Zendo Project, which has spent more than a decade supporting people through challenging experiences at festivals worldwide. I've volunteered and camped with them, and what stayed with me was how much it can help, in a hard moment, to simply have another person there. Not fixing anything, just being present and listening.

We worked with licensed therapist Marjorie Boggs Vazquez to develop our own version of that practice and train our volunteers. Now, Zendo and Sphinx Gate are exploring what a partnership might look like. The stewards aren't there just as a precaution, they're an invitation: if you want to go deeper, someone can sit with you.

And people did go deep. One woman came in weighing whether to leave the career she'd spent years building. On the platform between the sphinxes, she decided to take the leap and become a mother.

Another arrived deep in denial about an illness. What she found on the other side wasn't an answer. It was the ability, for the first time, to look at it honestly. 

Many found us afterward and shared what happened. What we heard again and again was that the space felt like the Temple at Burning Man, where people go to grieve those who have passed. The same reverence, a similar sacred energy. Except instead of the dead, it was for the living.

MS: One of my greatest passions is building shared awareness of what unprocessed experience does to people, and to the systems they run. In this future, it’s common knowledge, with a basic game plan for what to do about it. You’d learn it in school, the same way you learn to brush your teeth, and tools for it would be offered at every checkup, right alongside the blood pressure cuff.

A few places are partway there: Hawaii and Delaware have declared themselves trauma-informed states, and Alaska wrote early adversity and resilience into law, though most of that work targets children through clinics and agencies. 

That's the gap I'm hoping the Sphinxes can fill. Picture it: mini Sphinxes in town squares and parks, tea being served, music playing. A place people actually want to go, held by neighbors trained in peer support and built by local artists. Tending your inner world stops being something you ignore until it gets bad enough to need a specialist and becomes something a community does together. That’s the part I think actually moves the needle: people process faster when someone’s there to support.

Presently, we’re redesigning the minis for cities, because what works on the playa isn’t what works on a Tuesday in a town center. 

I also want to measure the impact. We’ve logged a few hundred tags so far, and the same handful of riddles come up over and over, but I want to know what actually shifts for people, and how long it lasts. If this is going to be a public health practice, it has to hold up like one.

MS: Looking at the world right now, it feels like humanity is in a grand hero's journey of its own, a time of crisis stacked on crisis, with a lot of people struggling and losing hope.

The NeverEnding Story built a whole villain that feeds off that feeling: “the Nothing”, the emptiness left behind when people stop believing. The more people give up hope, the more of the world it eats.

In order for the hero, Atreyu, to understand the Nothing, he first has to look within. That's the question the Sphinxes pose. As threshold guardians, they look into the heart of anyone who wants to pass and see whether they feel their true worth, if you don't, you get "lasered." The high stakes are no accident. The story is asking Atreyu, and everyone watching: what does it actually take to know yourself? 

The Sphinx itself is fascinating, it’s appeared across cultures for thousands of years, usually doing something important: guarding temples, tombs, cities, sacred spaces. The Greeks gave it a riddle, and I’m glad they did. There’s something playful about a riddle, it lets us get curious about something we don’t understand instead of being afraid of it. And I can’t think of a greater riddle to unpack than our own unconscious and all the unprocessed experience that can leave us feeling blocked and powerless.

I like to call it the riddle within: an invitation to pause and get curious about what's inside, because maybe we can't fully meet what's happening in the world until we're willing to understand what's happening in ourselves first.

Check out TheSphinxGate.org and follow @TheSphinxGate on Instagram to learn more. 

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