17. Tidal Mills
Tidal mills appeared along the coasts of medieval Europe, harnessing the natural rise and fall of tides to grind grain. These ingenious structures channeled seawater into reservoirs, releasing it to power waterwheels as the tide receded. Tidal mills provided a steady, renewable source of energy, even when rivers ran low. Their use represents one of the earliest examples of large-scale renewable energy in history, highlighting medieval innovation in resource management and technology.
