The History of Rome
Duncan recorded this while working in the fish trade, alone, with no co-host and no sound designer, and took the story from the founding myth to the deposition of the last western emperor in 179 episodes. It won best educational podcast at the 2010 Podcast Awards and has stayed at the head of the field for the fifteen years since. Seventy hours are indexed here. The first dozen episodes sound like a man in a cupboard, and he gets audibly better around thirty. What you get for the length is continuity: by the third century you know the families, and the collapse lands because you watched it get built.
Where to start. Episode 1. Fifteen minutes, and it is built to be the beginning.