Stone pillar

Stone Pillar are stone statue that Sonic can break.

Sonic the Hedgehog 2 (16-bit)
The pillars appear in Aquatic Ruin Zone where pillar rise up that Sonic could break them. Pillar appear in the water where the bottom of it fall to the ground where Sonic can get squash and die.

Other Media
In Adventures of Sonic the Hedgehog episode "Trail of the Missing Tails" a stone pillar is seen with Tails tide up to it by Dr. Warpnik in the Warp of Confusion.