This is utterly thirst quenching and refreshing, not to mention delicious and that's from someone who is not really a watermelon fan.  Try this, please, you won't be disappointed.  I came across it in a local gourmet store and once tasted I simply had to attempt to recreate its wonderful flavor.  If you're not convinced by now, bare in mind that it takes about 2 minutes to throw together and then you just chill it the fridge.  Brilliance!

1 watermelon, chopped into cubes

A large sprig of fresh mint, chopped

1/2 teaspoon of Rosewater

Chop up the watermelon. Chop up the mint leaves and combine with the watermelon.

Pour over the rosewater. Go slowly with this, you can always add more if you really want to but it's really rather like perfume.  A little is intriguing, too much is, dare I say, gauche.

Chill in the fridge for an hour for it's best advantage.