I knew this was going to be the tower of London before I even opened your post. The company that now runs the tower have gone mad with power.
It used to be that the Yeomen would guard the side entrances and patrol around the walls (it is still a functioning army barracks) and if you were serving military they would sneak you inside for free upon showing your military ID.
That was before the tour company build those ugly plastic walls at the front and replaced the yeoman with soulless rentacops.