Combine sugar and water in a saucepan.

Bring to a boil, then simmer until sugar dissolves.

Cool the simple syrup for 10-15 minutes.

Blend cooled syrup with hulled strawberries until smooth.

Strain the strawberry mixture if desired.

Slice one lime into thin rounds.

Place lime slices and mint leaves into four glasses.

Add strawberry simple syrup to each glass.

Muddle the lime, mint, and syrup.

Squeeze lime juice into each glass.

Add rum to each glass.

Pour sparkling water into each glass.

Add ice cubes, stir, and serve.