Imported models seem to be in a box

I have some pre-made “maps” (large models) that i have made.
I can import them just fine, but they seem to have a box around the hole thing,
I would like to be able to treat it as a map, and move around in it, but i cant,
please help

Pictures :

Take a look at this video: In your case the 3rd way would be perfect. :slight_smile:
When you use the 1st way, make sure that you disable “generate collision” + “one convex hull per…” in the import settings

Worked like a charm, Thank you