A hatch in the middle of moorland leads down to a short entrance passage, which then drop down into a larger room.
The main room was a backup receiving area for the Chain Home radar station during the second world war, I am omitting the exact location on purpose as its filthy and flooded to the ceiling and you’ll only end up getting as wet as I did or worse.
I have seen the hatch but never looked underneath. WIth it being a peat moor I assumed it would be full to the rim after more than 60 years