Using a program called Worldpainter, a builder by the name of lentebriesje is trying to recreate all of planet Earth in Minecraft. At a 1:1500 scale.
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That is a lot of blocks.
His Earth is based off this very large, very fancy 3D map of the planet, and while it doesn't include anything man-made, it does feature region-specific stuff like native trees, climate, etc. Plus, you know, this is Minecraft. You want buildings, you go build some buildings.
Currently broken up into separate maps for separate continents, he hopes one day to have a complete map of the planet for people to mess around with.
The recreation of the Earth 1:1500 scale [Planet Minecraft, via PC Gamer]