The opposite of 'nadir'. What is the highest point for each test side over their respective histories?
I'll make a weak attempt here to get the ball rolling.
Australia: Beating England in 1948, and also beating England 5-0 in 2006/07
India: Drawing 1-1 with Australia away in 2003/04
New Zealand: winning against Australia away in 1985/86.
West Indies: 'Blackwash' of England away in the mid-1970s.
Keep in mind, I mean 'test' sides. So Pakistan winning the World Cup in 1992 doesn't count.