In a small saucepan, bring the water, sugar, and blackberries to a boil. Reduce heat and simmer 15-20 minutes until the berries burst and the mixture thickens slightly, and you reach your desired consistency.
Strain the contents into a glass jar through a very fine mesh strainer while gently pressing the fruit to extract as much of that delicious juice as possible. Discard the solids.
For the Blackberry Aperol Spritz
In a rocks glass or wine glass add the Prosecco, followed by the Aperol, blackberry simple syrup, club soda, and finish by adding a few ice cubes. Garnish with fresh blackberries.
Notes
Your "parts" can easily be measured in ounces, or eyeball based on size of your glass.