I have always been equal parts fascinated and scared of caves. Imaging exploring on underwater!
From Penguin Random House:
As one of the most celebrated cave divers in the world, Jill Heinerth has seen the planet in a way almost no one has. In a workday, she might swim below your home, through conduits in volcanoes or cracks in the world's largest iceberg. She's an explorer, a scientist's eyes and hands underwater—discovering new species and examining our finite freshwater reserves—and a filmmaker documenting the wonders of underwater life. Often the lone woman in a male-dominated domain, she tests the limits of human endurance at every tight turn, risking her life with each mission. To not only survive in this world but excel, Jill has had to learn how to master self-doubt like no other.
Heinerth, Jill. (2019). Into the Planet: My Life as a Cave Diver. New York: Ecco.