The Cavern was first mentioned in the episode "Lost Our Lisa" when Marge throws out a roll of film and says it was from their trip to Carl's Dad caverns. In "Bart vs. Lisa vs. the Third Grade" Bart said "she (Lisa) wet herself at Carl's Dad caverns". The Simpson family once visited the caverns. When Bart realized it was a nature walk, he tried to escape. Lisa gave him a nickel in a water bottle to entertain himself and it worked. Meanwhile, Homer tried to chip a piece off of a long stalactite. However, the stalactite fell into the ground and the family followed it, with Homer getting stuck in the hole.
While Marge, Bart and Maggie were looking for the way out, Lisa told Bart a story. During the story, it was revealed that there were gold coins hidden in the cave. They eventually found the bag containing the coins, but suddenly, Rich Texan, Mr. Burns, Moe, Snake and his son Jeremy appeared, ready to fight and claim the coins for themselves. Marge then grabbed the bag and dropped it down a deep pit. After she dropped them, Mr. Burns attempted to climb down the pit to get the gold. However, everyone else realized how greedy they had been and went out to volunteer as a way of atoning for their sins.