Personally I’d say cave diving. I was contemplating between that and free climbing soloing but I honestly rather fall to my death than drown in a claustrophobic, dark, cold, silted up cave.
Yeah thanks, I meant the proximity flying with a wingsuit where they fly very close to the terrain. I live close to a mountain where they are doing this. The videos are stunning but we hear about accidents regularly in local media. If something happens your done. No thx: https://youtu.be/QKMkhCsgsas