at Calke Abbey. The servants were not to be seen, so a tunnel under the grand house went from the house to outer buildings where wine was stored and other goods for the kitchens. They had to travel quite a distance underground from one to the other so they weren't seen above ground by the family living in the house at that time. The electric lighting would have been added in more recent years. I guess the servants had candles to see where they were gong.
Beautiful light, capture! Amazing, may be that's where Walt Disney got his idea for the Magic Kingdom at Disney World. The cast members travel under the theme park as not to be seen.
I'd enjoy a wander through here.