This sounds SO refreshing and really good. I'm going to try making it this weekend. If you ever buy blackberries at Costco and can't eat through them all, this drink is perfect.
6 cups water
3 cups fresh blackberries
1 cup sugar
2/3 cup fresh lime juice (about 4 limes)
8 thin lime slices
fresh blackberries (optional)
Place 1 cup water and 3 cups blackberries in a blender; process until smooth.
Press blackberry puree through a sieve into a large pitcher; discard seeds. Add remaining 5 cups water, sugar, and juice to pitcher; stir until sugar dissolves. Place 1 lime slice and a few blackberries, if desired, into eat 8 glasses; pour about 1 cup limeade over each serving. Yield: 8 servings.