To make the Moscow Mules combine the vodka, cranberry juice, lime juice, ginger simple syrup, and sparkling water in a large container. Mix well and add 6 cups of ice.
Add in the lime wedges and fresh cranberries and serve.
To make the simple syrup combine the water, sugar, and ginger in a small saucepan over medium high heat.
Bring the syrup to a boil and boil for 5 minutes, stirring frequently. Remove from heat and cool completely.