Abandoned WW2 bunker in Switzerland disguised as rocks

I can imagine a very exhausted and confused Swiss soldier who got mixed up with his bunker and a pile of rocks and is just banging on the side of it waiting for someone to open it up when it's literally just a pile of stones

Hide-a-key totally stole thier idea from this huh?

Remember though, this is Switzerland we're talking about here, so... "abandoned."

A neutral bunker.