Glass bottles, left in a metal box on the front porch before sunrise. You would hear the clink of the bottles and the hum of the truck at 5am if you were a light sleeper.
The cream would rise to the top of the bottle and my grandmother would skim it off for her coffee. The milk tasted different than store milk. Richer, somehow. Or maybe that is just how memory works.
We left the empty bottles out and they came back full. It seemed like magic when I was five. An endless supply of milk that appeared while you slept, like the world was taking care of you.