History of the old black and white post. What is it?

I pass by this post nearly everyday but I can’t figure out what it is. You can see it clearly during the winter but it’s covered up by trees during the summer. It’s at the Hydebank junction near Newtownbreda. They cleared a lot of trees last week and they might remove it soon. I’d like to know what it is before it disappears forever. It kinda looks like an old bus stop or something? It’s quite far up the bank so it’s an odd place to have something up there.

by Enirehtac