At the entrance of Dublin castle in Ireland is a gate with sharp spikes on the end of them. As the story goes if someone was accused on treason in Ireland hundreds of years ago they would be beheaded, and their heads would be displayed on these pikes to warn all others that treason would result in your head getting chopped off haha
If stories like this are interesting to you I suggest doing the different walks available while traveling. Haunted walks, history walks, pub crawls, these are all really cheap ways to meet new people, learn cool stuff, and have a great time. And they usually just take a couple of hours.