4 1/2 cups coarsely chopped, seeded, peeled cucumbers (about 4 medium)
4 cups cold water
2 cups Ice cubes
1 cup sugar
2/3 cups fresh lime juice
2 large pinches of salt
Additional ice cubes
Combine 2 1/2 cups cucumber, 2 cups water, 1 cup ice cubes, 1/2 cup sugar, 1/3 cup lime juice, and 1 pinch salt in a blender. Blend until sugar dissolves and mixture is smooth but slushy, about 2 minutes. Transfer mixture to a pitcher. Repeat with remaining ingredients.
To Serve: Place additional ice cubes in 8-oz. glasses and fill with drink.