The 99% invisible is a brilliant podcast. I was alerted to the so-called Thomassons. These are architectural artefacts who have lost their function, but, and this is crucial: are still being maintained. For – essentially – no reason whatsoever. It is surprisingly hard to find images that exemplifies it. What I find fascinating, is the “used to be useful – now it is useless – we paint it anyway”. You could, I suppose, call it architectural evolutionary dead ends. Perhaps they are a comment on our society, but the point is they seem unconscious and somehow invisible. Look for them, they are extinct, architectural species.