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I'm trying to get the "On a Rail" achievement, but I can't seem to go far enough.
Each block is the equivalent of one meter. Given that there is 1000 meters in 1 kilometers, you would have to build a track that spans 1000 blocks in one direction.
1 km is 1000 minecraft blocks. I tried creating a circular track, like so:
However this did not work, as the achievement states you must travel 1000 blocks from your starting point. So, the only reasonably viable method to the achievement would be this:
If you're doing it in creative, it's rather easy - took me around 15 minutes to build the rail, and 2-3 minutes to ride it. If you're doing it in survival, I'd recommend the following tips: