While digging in my bedrock-level mine, I found a ravine a few layers up (the whole thing has a lava lake at the bottom, noticed it dripping through), and an abandoned mine a few layers above that. I'm looking through it for some chests, and I just came across a section where it's intersected by a small ravine. I looked up, and there's water pouring down through a large crack in the ceiling, and I can see daylight.
I didn't see how that was possible, considering I'm at around layer 30. I suddenly remembered that I noticed a very deep, very faintly lit crevice off the coast of my house, too deep to explore without drowning. I think that's where I am right now. This is seriously so cool.
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