Was walking along the boardwalk at the beach with my wife and saw this. She was like what's that? I told her Rock balancing
Source
https://en.m.wikipedia.org/wiki/Rock_balancing
Rock balancing or stone balancing (stone or rock stacking) is an art, discipline, or hobby in which rocks are naturally balanced on top of one another in various positions without the use of adhesives, wires, supports, rings or any other contraptions which would help maintain the construction's balance.