here, a (10-15 year old) picture of some thing installed in the uppermost part of a tower of the village i used to go some summers

the only logic explanation i can think to "what is this thing" is that it is some kind of artifact to defend against attacking dragons. rusted because obviously there are not dragons anymore around there. sadly.

Scientists at Hunter College in New York have determined that not only do cats enjoy sitting in boxes, they also enjoy sitting inside the optical illusion of a box. (source) (publication)