From Sonic Retro


Minecarts made their first appearance in Under Ground Zone from Sonic the Hedgehog 2 (8-bit). The player can jump into a minecart to start it moving, and ride it along the tracks laid throughout the stage. If the cart rolls into spikes, it will destroy them completely. The cart will keep rolling until it hits a wall, at which point it will break apart and disappear.

Minecarts also appear in Lost Labyrinth Zone from Sonic 4 Episode 1.