The rest of this site looks up. This once, we go the other way — straight down, from the surface of the sea to the deepest point on Earth. Every depth is real, and to scale. Take your time.
Light is still bright, water still blue. A diver on a first open-water certification is cleared to about here. Everything you've ever swum in fits above this line.
Below this, ordinary scuba turns serious — nitrogen starts to fog the mind like three martinis, an effect divers call "the narcs." Sunlight is dimming, but the world is still lit.
Red light vanished a while ago; down here everything is blue-grey. A blue whale, the largest animal that has ever lived, feeds around this depth and deeper — it could be beside you now and you'd barely make out its shape.
This is the floor of the light. Below 200 metres, too little sun reaches for a plant to live. Everything deeper eats what falls from above, or eats what eats it.
Ahmed Gabr reached 332.35 metres off the Egyptian coast in 2014 — a descent that took about twelve minutes and an ascent that took nearly fifteen hours, to keep the change in pressure from tearing his body apart. No one on open scuba has gone deeper and returned.
Guinness World Records, 2014.On the floor of Monterey Canyon sits a microphone that never sleeps — a deep-sea hydrophone operated by MBARI, wired to shore, carrying the sound of the deep ocean up to the surface and out to anyone who wants to listen.
Snapping shrimp, the hum of a distant ship, sometimes the low moan of a passing whale. This is the sea at 891 metres.
The twilight ends. From here down it is permanent, total darkness, broken only by the animals that make their own light. A sperm whale hunting giant squid dives through this black on a single breath, to 2,000 metres and deeper.
Two and a half miles straight down, in water that never rises above freezing and presses at nearly 400 times the weight of the air you're breathing now. The ship has been resting here since 1912 — longer on the seafloor than she ever spent afloat. You've descended past her, and the bottom is still nowhere in sight.
Wreck depth ≈ 3,800 m, North Atlantic.The German battleship, sunk in 1941, lies deeper still on the abyssal plain. Down here the seafloor is a flat, cold desert of mud that covers more of the planet than every continent combined — and almost none of it has ever been seen by human eyes.
Named for Hades. Below this depth the seafloor cracks into a handful of vast trenches — the deepest places on Earth, and among the least explored anywhere. More people have walked on the Moon than have travelled to the bottom of one.
A young snailfish, pale and almost translucent, caught on camera in a Pacific trench in 2023. Scientists think this is very near the hard limit for any fish — deeper than this, the pressure warps the very proteins that hold a body together.
University of Western Australia & Tokyo University of Marine Science and Technology, 2023.The bottom of the world. Nearly seven miles down, at the far end of the Mariana Trench, the pressure is over a thousand times what it is at the surface — a weight like a small car pressing on every square centimetre. It is utterly dark, a few degrees above freezing, and still: there is life here, tiny and patient, in the deepest cold on the planet.
You have descended the full height of the ocean. Mount Everest, turned upside down and lowered into this trench, would still leave more than two kilometres of water above its peak.