2 bottles (25 ounces each) blood-orange juice, chilled
3 cans (12 ounces each) natural orange soda, such as San Pellegrino Aranciata, chille
3 tablespoons fresh lime juice
8 ounces light rum, such as Appletons
5 dashes bitters
1 blood orange, or orange, cut into 1/4-inch-thick wedges and frozen
Fill ice cube trays with 1 1/2 cups orange juice, and freeze. To make punch, stir remaining orange juice, soda, lime juice, rum, and bitters into a 16-cup punch bowl. Before serving, add frozen orange slices. Add ice cubes as needed to keep chilled.