In a small bowl add orange zest and 4 sprigs of mint. In a second bowl add the lime zest and ginger. To a third bowl add 3/4 cup of the raspberries.
In a pot mix the sugar and 3 cups water. Put over medium heat and bring it to a boil, then evenly divide the sugar syrup among the 3 bowls. Stir each to mix and let cool to room temperature. Pour each mixture into jars or syrup containers and refrigerate until ready to use or up to 2 weeks.
Set up the Spritzer Bar:
Set out chilled bottles of sparkling water. Put out plenty champagne flutes or wine glasses. Let people create their own Sparkling Spritzer by mixing about 3 tablespoons of a flavored syrup with some seltzer water and a shot of vodka or Prosecco, if desired. Garnish the drinks with mint sprigs, orange slices or lime slices.