In a large pot, combine black tea, lemon and orange zest, and boiling water. Let steep 8 minutes. Remove tea bags and let cool to room temperature, about 2 hours. Serve over ice with lemon and orange slices if desired.
This drink can be refrigerated for up to 3 days -- add garnish and ice before serving. Try using canning jars in place of pitchers or glasses for a casual party.