The entrance to Veryovkina is a short 20 metre abseil down this teardrop-shaped pitch. It’s hard to believe that this unassuming hole in the ground surrounded by lush green foliage is the start of the deepest-known cave in the world. Only another 2,192 metres (7,192 ft) to go to reach the bottom. Each two week journey underground begins and ends right here. When going in, explorers are excited and maybe a little anxious about what lies ahead, but when coming out this shaft and the view to blue skies provides a sense of relief and achievement.