walkable walls?

i'm sorry if i posted it on the wrong thread. i just want to know how to make walkable walls like what tha_chump and zarniwoop did for the minas tirith.

make them destructibles and click the walkable then it's walkable. Another way if u dont watch it to be destructibles u can use invisible platforms on the wall. You still need to use pathing blockers to block the side of the walls so units dont walk off it.

I once made a tutorial about this. It's located here.