Mountains/Subterranean

[archanison]

Mountains - Generated about like water; impassable terrain; can build tunnels/caves using explosives
Subterranean Layer - generated with mountain, can contain ore patches and even biter nests. will allow for passing through a mountain by foot, car, or train.

[BlueTemplar]

https://mods.factorio.com/mod/Decu

A scenario where you can go underground and dig through rocks. You could find treasure chests, patches of ores... or big caves full of bitters! Credit to original creator Decu

[archanison]

yes, but this is a scenario, so it's not even really a mod.

[BlueTemplar]

So ?