Missing Chunk of Land

[Gariandos]

So I've noticed outside of Whiterun around the fields not far off, there's one area missing a large chunk of land. I.E., there's rocks and patches of land floating where the hill used to be. Walking over it causes you to drop down into the ground below it but thankfully it levels out as you get onto the flatter part of the plains. Only problem is I have not the faintest idea of what mod is causing it, and I haven't installed any mods that causes changes to the fields of Whiterun, as far as I know.