Michael Grab balances impossible rock structures with gravity, practice, and patience. No glue. No hidden tricks. No additional supports.

Grab is a professional rock balancer, and he’s spent over a decade improving this skill. His work started getting the internet’s attention just a few years after he started pursuing the art form in earnest. How does he make these impressive temporary sculptures? “He always works backward, picking the final rocks first. The bigger the top rock, the more impossible the structure will look when he lets go.”

Please note, however, that Grab always knocks down his heavy, precarious sculptures after he photographs them. He wants to make sure that no animals or people are injured by them.

In this Wired Obsessed video, he demonstrates how he picks rocks, and then makes diligent micro-adjustments as he stacks and holds them in place. His goal: Find their centers of mass to build freestanding structures that exist anywhere from a few seconds to a few days (if it’s protected and not out in the wild).