Sótano de las Golondrinas, or Cave of Swallows, is the largest pit cave in the world — an over 1,200-foot drop from top to bottom. It's also home to thousands of birds, who spiral out of the ...

Near etchings of indigenous Taino deities, archaeologists in Puerto Rico discovered Christian inscriptions in a cave on Mona Island. Since at least the twelfth century, indigenous Taino people ...