When we last left our hero, he’d found a ravine. After orienting myself, I built a bridge across the ravine and crossed it:
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Crossing the Ravine
There was a natural cave on the other side; I wandered through that, dug a corridor through the wall at the end (going straight rather than up or down, I’m not sure why), and then I encountered a second cave:
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There are water sounds on the left
I heard water on the left, which kind of scared me: I didn’t have a good feel for the dynamics of water in the game, and I also had no idea whether I was even under land at all. So I went forward some, and found:
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Glad I'm in peaceful mode
my first monster cave! Or it would have been a monster cave, but I was in peaceful mode. Nice mossy rock. After that, I decided I’d been in caves enough, so I dug some stairs up, and eventually made it out to a desert.
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Heading back up
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More desert!
As you can see, I stuck with my previous idea of building a trench so I’d be able to find the entrance again if I got lost.
But a funny thing happened as I was digging along in that trench: at one point in my digging, the sand crumbled, and:
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A Cave!
Gee, what’s this cave doing here? It’s plenty deep, too, and had a lovely waterfall-filled pool once I got down to the bottom.
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Quite a bit further down to go
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I love this waterfall
There was a lot of space down there; in particular, heading a bit to the right, I found a further extension of the cave with underground rivers of lava and water next to each other.
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Rivers of Lava and Water
I tunneled around behind the lava to explore some more (that’s how the crafting table got there); I also went in different directions from the earlier room. (Which had a lot of coal and some amount of iron ore, incidentally.) I was a bit afraid of getting lost, though, and the spaces were a bit too open and free-form for me to feel like exploring them just then, so I climbed my way back up to the desert and went back into my original cave complex. Also, at some point I went aboveground back to where I’d first started digging way back when, after first figuring out where I’d made turns underground so I’d be confident I wasn’t heading in the wrong direction. It felt like I’d traveled forever when I was doing this underground, but aboveground the distances proved to be much shorter!
When I got back to the room where I’d heard water, I decided I wasn’t scared of that any more. For whatever reason, rather than digging straight through the wall in question, I dug up a bit, and that turned out to work well: I ended up just above a nice little river.
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Another underground river
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The latest update has added a squid here!
I didn’t verify it this time, but I’m fairly sure that, eventually, I hopped over that river (via the bridge you can see in that picture) and traveled through a cave system that was on the other side to get back to that lava flow I’d seen earlier. So clearly this whole area is riddled with caves, and I probably haven’t come close to exploring them all. In fact, there were enough that I was feeling a little burned out from the caves; I decided that I’d go back to the original entrance that I’d dug and hollow that out into a real house.