Cave Entrance (IMAGE) University of Texas at Austin Caption This is the entrance to the cave in Puerto Princesa Subterranean River National Park in Palawan, Philippines. The researchers used a stalagmite growing from the floor of the cave to learn about rainfall in the Philippines during the Younger Dryas. Credit Jud Partin Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.