There have been a few other topics like this (for examples):
https://www.chess.com/forum/view/game-showcase/quadrupled-pawns
https://www.chess.com/forum/view/general/quadrupled-pawns
https://www.chess.com/forum/view/general/have-you-seen-a-game-with-quadrupled-pawns
I've had quadruple pawns twice in blitz games. What's the most you've ever had?