hi there last night i was borred and so started hunting around the web for minecraft irl one of the things i found were the Naica crystal caves in mexico. these series of massive underground caverns contain gigantic gypsum crystals. anouther thing i found was a talk on massive underground rivers that run through ravines similar to those in minecraft these rivers flow far below the surface and are massive, with many flowing into vast unexplored underground lakes. within these caves, it would be awesome to find some form of naturally glowing rock formation to provide light and ambiance these cave structures would be found really deep underground and could stretch a great amount of distance. this would be a personal favorite idea, as i really really want to go rafting down an underground river i am open to other ideas