At first I got really excited thinking I’d found a secret, but then I realized I was running around the hills behind the scenery when I looked through the back of the Dirac Corrugation walls. Also I could get quite far in them thar hills; I made it all the way back to behind the start area before I got bored - it was well spooky.
You can totally go up that beam no problem (at least in 1.31).
By the way that would be an excellent place for a secret area (seriously those rocks are like a goal post, and the goal is secrets).
PS: I found where the signal actually comes from.
It comes from this spooky tower.
If you need to make a cool mordor looking area, your job is basically already done.
There’s something to be said for seeing a tall structure in the distance and running over ominous black hills for 10 minutes before reaching its colossal bulk floating over a black void.