Unlike the vertical waterwheel familiar from later industrial milling, the horizontal-wheeled mill, sometimes called a Norse mill or tidal mill depending on its setting, worked on a simpler principle: water was channelled through a narrow chute onto paddles mounted horizontally beneath the millstone, spinning the upper stone directly without the need for gearing. This design was extraordinarily common across early medieval Ireland, and hundreds of examples have been identified archaeologically, yet individual sites rarely attract much attention.