Stir together 2 cups water, the sugar, and the blueberries in a medium saucepan over medium-high heat. Bring to a boil, reduce heat, and simmer for about 5 minutes, stirring until the sugar has dissolved and the blueberries have burst. Note: you can mash the blueberries a little to release more of the flavor and color.

Remove the syrup from the heat, add the basil, and cover. Steep for 20 minutes. Strain through a sieve and discard the solids.

In a pitcher, stir together the syrup, lemon juice, and cold sparkling or still water. Enjoy over ice and garnished with a lemon slice, additional blueberries, and/or basil leaves. Add a splash of vodka or local fruit wine for a refreshing cocktail!