So here was quite a special dive experience. All over the Yucatan are underground fresh water ‘wells’ or cenotes. They are really huge flooded limestone caverns. Many are available to dive – I did just two dives round a single cavern system

Almost impossible to get good photos because of the complex lighting conditions, but hopefully you get a sense of it from these examples

Essentially treated as wreck dives, with a permanent penetration line laid in, following the ‘thirds’ principles on air (third to get in, third to get out, third for emergency), and never being more than 40 m from a light source.

Many parts of the cave were very dark, so it was all on torches.