Wales play England every year in the Six Nations, so surely there's nothing they don't know about the English ahead of Saturday's World Cup clash?
Well, maybe not. Wales travel to Twickenham to take on the 'old enemy', with both teams having won their opening World Cup fixtures against Uruguay and Fiji respectively.
So what do Welsh fans need to know about England and its rugby culture? Sit back and let BBC Scrum V's Phil Steele explain.