Hey guys happened to catch part of a Weird US episode on the History Channel the early today. The Marks explored some giant lead mine somewhere. They seemed to be open to the public for tours and all that. I didnt get to watch much of it cuz the Travel Channel's Passport to Europe with Samantha Brown was on at the same time and sorry miner dudes but Samantha Brown ROCKS! I cant get enough of her shows Passport to Europe and Great Hotels... Anyway the part I saw featured a mine that has since been mostly filled with water. Its now used as a "certified" skubadiving practice site or whatever. The water is crystal clear and you can see right to the bottom in alot of places. With skuba equiptment they explored the submerged tunnels with all the old mining tools, carts, ect, still down there. Might wanna look into the next airing of this episode... i think you can order it on dvd if its not coming on again.
http://www.historychannel.com/weirdus/