Talk to Bill Stone about that - he's been one of the preeminent cave explorers and they've been working towards exactly that: https://stoneaerospace.com/ https:

Talk to Bill Stone about that - he's been one of the preeminent cave explorers and they've been working towards exactly that: https://stoneaerospace.com/ https://stoneaerospace.com/ - look at Prometheus and Archimedes in particular.