This Python script takes in a heightmap image and turns it into an Unknown Pleasures album art style image. There are a bunch of sliders to adjust the output to your liking. I got some inspiration from garrettdreyfus's project, but I really wanted a result that more accurately represented the original art style.
A recreation of the original cover:
And the corresponding input heightmap (I also messed with the sliders a bunch):
A map of the world with elevation:
California with random noise: