Underneath the school

When I came out of the oakwood after doing a litter pick, I noticed that the bottom gate to the secondary school was open so I ventured in, thinking that I could maybe exit the campus at the other end. (No, as it turns out.) It amazes me that a huge building can rest of a few rows of brick pillars. While this style of archtiecture is now seen as obsolete it still seems to me to be a great feat of engineering.  We tend to marvel at railway viaducts, so why not this? (Wow!)