The Skull Cave, also called the "Skull", is a very creepy Cave featured in the 1997 cartoon film Pooh’s Grand Adventure: The Search for Christopher Robin.
When Pooh, Piglet, Rabbit, Tigger and Eeyore first arrived looking for Christopher Robin, it was very scary and big. As they split up to find Christopher Robin, Rabbit fell down a hole, Tigger gets scared away by bats, Piglet slips on rocks and Eeyore, who was wearing a scary-looking mask on his face runs with Piglet sitting on his buttocks the other way. When they ran into each other, they were scared away by Pooh, mistaking him as the Skullasaurus.
However, when they emerged, it turned out to not be so scary after all, as with all the others.