A gentle, quasi-insult from more innocent days, when climbing up a thing just to get to the top of it was the giddiest of thrills. "I’m the King of the castle/and you’re the dirty rascal!" you’d shout from the top to your fellow climbee, and genuinely, you couldn’t have felt king-ier if you tried. Try calling someone a "dirty rascal" these days and seeing where it gets you.

Interestingly, even girls shouted "KING of the castle". Presumably it’s not considered a very queenly thing to do, climbing stuff, though HRH would probably be more popular if she did occasionally tuck her skirt in her pants and got a boostie up the side of a bus shelter.