13 years ago, I uploaded a bunch of random height maps I generated with fractal flame algorithms. Even at a time when we didn't have many options, those height maps were probably among the weirdo options that nobody asked for.

Still, I also received messages praising the different gameplay possibilities offered by those maps. And it was also fun watching the AIs fighting on these ridiculous maps.
Anyways, at that time I generated them at the largest resolution I could (2048*2048). However, I see that now OpenTTD supports even bigger maps, and JGRPP, even larger. People are creating 8192*8192 height maps and scenarios.
And, surprisingly, most of the original fractal configuration files are still extant, so I figured out that I can regenerate them at larger resolutions...
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For the Curve Lands, their main feature is the long winded islands. I make sure that when you downsize them to the original size (usually 2048*2048), the islands are still connected as before, but the map can also be played at higher resolutions without the annoying aliasing effects.
Curve Land 1 (Uploaded!) Curve Land 2 (WIP)
Curve Land 3 (Uploaded!) Curve Land 4 (2k version Uploaded!) -------------------------
For those Fraclands, I don't think they have much defining features, they just have weird mountains and coastlines. So I'll generally just rebuild them to larger sizes and see what happens.
Fracland 1 (WIP) Fracland 2 (WIP)
Fracland 3 (WIP)
Fracland 4 (WIP)
Fracland 5 (Uploaded!)