Before making any rash decisions like “I should use my entire supply of iron ore to experiment with my own rail system” I decided I’d start by looking for horses. I walked as far in the distance I call “east” as I could in half a day, then walked back.
I found 7 giraffe corgis, 17 zombies, 2 very angry skeletons with a full set of arrows, some funny glowing boots, lots of gold armor, and something in the neighborhood of 72 ducken. (I think they’re breeding in my caverns.)
Tomorrow I try north, though north is mostly water.