I asked Husband which would travel best: a square cake or a round one. 'Hm,' he stroked his chin thoughtfully. 'In school I learned that they stopped building square towers on castles and built round ones instead because the square edges were vulnerable to attack by catapult.'
So, in case on its journey north it is attacked by marauding Englishmen, the cake had better be round.
It's a good job Husband paid attention in class all those years ago.