Notes

To most of us, the caving trips of Marcus Thomas sound like crazy endurance tests. But for extreme cavers like Marcus, this latest one is a dream come true. He and his team-mates are hoping to prove that the Bulmer cave system is much larger than previously thought – and today might be the day. If they pull it off, the team will make history. It all depends on the journey of a small trickle of green dye.