There used (30 years ago) to be a pub N of Liverpool called the "Duck Inn". The main entrance to the bar had a flight of about three or four steps down to the bar floor and a big oak beam at head height. If you were looking down at the steps and didn't duck as you went in, you banged your head on the oak beam. You could sit at the bar and watch for new patrons as they got bonked on the way in. Only bar I ever knew where you could get a headache before you got a drink.