terrain split

Tool: http://kostiantyn-dvornik.blogspot.com/2013/12/unity-split-terrain-script.html Use it code

That's a big issue. I've been looking at that myself. There are extensions in the Asset store that look like they'd be helpful.

In case you're still looking for an answer . . .

I have just released an editor extension that splits terrains; it's called the Terrain Slicing & Neighboring Kit and is available on the asset store for 5$. You can divide your terrain into 4, 16, 64, 256, 1024, or even 4096 smaller terrains. Trees, textures, etc are all replicated. Have a look at the following forum post for more info: link text