Shining a light in the Underworld (Xibalba, as the Mayans call the center of their culture and mythology), these stunning images from diver and award-winning photographer Martin Broen transport us into a place that few cave divers can reach a world accessed from cenotes, water- filled gateways to labyrinths of tunnels that create the longest underwater cave systems on the planet. Over several years and multiple diving expeditions, Broen has captured over 250 different cenotes and caves, diving through mazes of pitch-dark tunnels and bringing photographs from his explorations back to the surface. Paired with images of startling otherworldly beauty, Broen s engaging text guides readers through the depths of the mysterious Yucatan cenotes that have taken millennia to form: from dramatic sinkhole entrances to caverns filled with rainbow-colored stalactites and stalagmites; from the caves formation and spectacular features to the time capsules of ancient fossils; from how cenotes were a source of life for ancient peoples to their critical environmental role today as a life sustaining component for the region. With contributions based on their own experiences in cenotes by National Geographic photographer Paul Nicklen, as well as leading underworld photographer and marine ecologist Alex Mustard, this volume beckons divers, cavers, and armchair explorers to explore a uniquely dangerous yet beautiful and essential underwater world.