Seen in the domes above Corona Arch.

The semi-circular arrangement of stones in the foreground does not look natural. And there seems to be stones stacked atop the "cave." This is the only picture of the thing I have. The shadowy "cave' is about ten feet (3 m) wide.

A color image would be nice, but this was shot with white balance set to "fluorescent lighting," causing the color to be "puke pink.".