The Bowl

You're walking along the edge of oceanside cliffs when suddenly the cliff gives way as if a giant has bent down and scooped an enormous crater out of the cliffside. Down below, there's another crater where water has filled up, pooling to stillness several yards blow. Outside the Bowl, the ocean waves still slap against jagged rocks, moving relentlessly in their endless back-and-forth dance, but inside the Bowl, the water is perfectly calm. There's an eerie feel as you try to get a better look at the smooth surface of the water, but sudden vertigo almost pitches you headfirst over the edge. It will take several minutes, but you'll follow the curve as it bends back toward the woodlands, eventually stretching around out again into the lonely cliffs on the other side of the crater.

Nothing lives long if it ends up in the Bowl. Unlucky fish that cross over during a tempest will find themselves without sustenance and float to the top in death soon enough. Land animals (and people) that fall in are liable to drown before a rescue can even be attempted, let alone executed. Presumably there's oceanic plant life down there, but even that is anyone's guess since it's yet to be explored. If nothing else, you can be certain to find microbes and bacteria after a dive into the Bowl - except you'd never make it out alive to show anyone.

People will have a number of fantastic tales in the future, but the truth is that it was created when bombs blasted into the cliffside with mistaken coordinates. The bombs created the massive hole in the cliffside, as well as the water-filled one below it. Nature did the rest of the work as water surged into the hole immediately upon its creation, resting days later when it reached its limit, wherein it found the stillness it's known for today.