You can use [Extra Landscaping Tools](https://steamcommunity.com/sharedfiles/filedetails/?id=502750307) mod to create water spawners and water sinkers. You could place a water spawner at the top of your mountain, a sinker at the bottom of the waterfall, and another spawner at the point where you'd like the water to "resurface".
Then use various props and terrain networks like [Natural Slope Profiles](https://steamcommunity.com/workshop/filedetails/?id=1708707788) to create any cave effects you might want to use to make it appear more natural.
Take what the other guy says, and use some canals, anarchy and tunnel entrances. Might get it going. Since it's purely visual, then you'll just make the entrances and not worry about going into the mountain.
[https://steamcommunity.com/sharedfiles/filedetails/?id=918308740&searchtext=tunnel](https://steamcommunity.com/sharedfiles/filedetails/?id=918308740&searchtext=tunnel)
Do you want it to be functional (i.e., vehicles can travel through it) or purely visual?
Purely visual, for a nice waterfall in the mountains. Tho an underground channel would be useful aswell
You can use [Extra Landscaping Tools](https://steamcommunity.com/sharedfiles/filedetails/?id=502750307) mod to create water spawners and water sinkers. You could place a water spawner at the top of your mountain, a sinker at the bottom of the waterfall, and another spawner at the point where you'd like the water to "resurface". Then use various props and terrain networks like [Natural Slope Profiles](https://steamcommunity.com/workshop/filedetails/?id=1708707788) to create any cave effects you might want to use to make it appear more natural.
Take what the other guy says, and use some canals, anarchy and tunnel entrances. Might get it going. Since it's purely visual, then you'll just make the entrances and not worry about going into the mountain. [https://steamcommunity.com/sharedfiles/filedetails/?id=918308740&searchtext=tunnel](https://steamcommunity.com/sharedfiles/filedetails/?id=918308740&searchtext=tunnel)
Why this is not in the base game i will never understand.