bbc.com/news/magazine-40558067 Two days in an Underwater Cave Running out of oxygen Three months ago, Xisco Gràcia experienced what he describes as every diver’s worst nightmare - he found himself in an underwater cave, relying on an air pocket for survival. As hours turned into days he realised he might not be found in time. On Saturday 15 April, Xisco Gràcia slipped into the water in Mallorca for a routine dive. The geology teacher spent most weekends exploring and mapping the island’s complex system of underwater caves.