In other words, the contents of these two freezers constitute a biological repository unlike any other in the world. The cave microbiome—the community of microorganisms that has adapted to life inside caves—remains largely unexplored. “We took great care to prevent contamination by surface microorganisms that we ourselves might have carried into the cave,” Paragkamian explained. After emerging from the cave, Paragkamian still had to hike for two hours to reach the expedition’s vehicles, which could not travel any farther. But one thing already seems certain: in the years ahead, the scientific community is likely to hear much more about the remarkable discoveries hidden for millions of years inside Gourgouthakas Cave.