http://www.filedropper.com/weirdwall (replay link, always use ublock!)
The ling on the bottom start location can go inside the base but not outside. Tried with CC also but that was solid wall.
I was researching how walls could be built on this map when i found this. I thought it was ling tight first, but when trying from outside to in it was not :'D
As most of you may know, this page: List of Unit and Building Sizes is used to check whether buildings to buildings are solid wall, however there is no such info vs doodads/terrain.
Fun fact from this is that you have to check your walls on new maps from both directions :D