Wouldn't surprise me that the "site" didn't pop up on the internet by conspiracy theorists claiming a UFO crash landed there and they were performing experiments on them because of it's secrecy.
I arrived at the site just after the dome was assembled, our company who specialised in TV & film scenery had the job of completing all the interior with a slide etc, when we got there we did not know exactly what the programme was about, walking around looking for the canteen I went past an open trailer & all the Tubby heads were on a long trestle table all in a row, my kids were little then so next day I took a camera for a photo ( no phone cameras then) and I got spotted and had a lecture about security etc for when the programme went on air so we all had to agree to keep stum
