Cenotes are a unique and delicate eco-system and deserve a respectful touch. We shot this video on breath hold with minimal equipment in several cenotes over several days and for each different one, we asked permission of the owner and whether we could touch the environment or not. In some cases, it was clear it was just rock or sand or sunken trees, but some looked liked stalactites – which are fragile and should not be touched. Turns out most of these were petrified stalactites, which had become solid rock and were fine fine to touch, long as we were mindful. In general, though, of course it's best not to touch anything when swimming (or running) in environments you don't know well. We tried to inform ourselves best we could and when in doubt, we stayed well clear of formations we weren't sure about – it's obviously not worth risking a unique environment for a video. Sofía Gómez Uribe is a world record holding freediver and highly trained athlete; probably best not to try and recreate this without serious training, and the type of safety in place that we had. Music is "Brash Gentleman" by Tomas Herudek.