I was just inside the mines...not for the faint hearted! First of all, you have to climb down a handmade (made from tree branches--Ala Gilligan's Island) ladder about 70 to 80ft down into the first section, and then it spiderwebs out from there. You can go down further, but i wouldn't recommend it because of the lack of oxygen and possible instability.
It was fascinating, weird, fun, scary and surreal all at once. But the climb up to the Larimar mine requires an SUV with 4x4 if wet, if dry, any SUV or truck can make it, but not a car. They look like this:
[video=youtube;0oCtWnxxCeQ]https://www.youtube.com/watch?v=0oCtWnxxCeQ&t=34s[/video]