Adjust oven rack to the center of the oven and preheat to 350 (175 C) degrees.
Spray a nonstick 12-cup fluted cake pan with cooking spray or lightly coat with olive oil.
Put the citrus zests and the sugar in a large bowl. Use your fingers to gently crush and coat the zest with sugar (your hands will smell amazing). Add the flour, baking powder, salt and baking soda and whisk until blended. Stir in the cranberries.
Lightly beat the eggs in a medium bowl. Add the milk, then whisk in the olive oil in a slow stream until blended. Pour olive oil mixture over the dry ingredients, stirring until the batter is smooth. Pour the batter into the prepared pan.
Bake 55-60 minutes. A toothpick inserted into the cake should come out dry.
Cool the pan on a rack for 2 hours before unmolding.
Make the glaze:
Whisk the sugar with the milk until smooth. Drizzle over the cake. Use a fine grater, like a Microplane, to grate orange zest over the cake. Cut into slices and serve.
You can also make this cake in a 9-inch springform pan. Coat the pan with oil and line the bottom with a circle of parchment paper. Bake time is the same.
Leave the berries whole, or coarsely chop half of them in a blender or food processor for interesting texture and color.