Heat 1 cup of water and 1 cup of sugar over medium heat, stirring occasionally, until sugar is dissolved

Add 1 cup blueberries, bring to a boil and then turn back to a simmer for about 15 minutes.

Strain syrup through a fine mesh sieve.

Set aside to cool

Squeeze lemons until you have 1 cup juice.

Once syrup is cooled, place it in a pitcherr and add lemon juice.

Add 4 cups cold water.

To serve, add ice to each glass, pour lemonade, and garnish with a lemon slice and/or blueberries.