Windmills vs Watermills: A Complete Guide to Historic Mill Types
When we think of mills, many of us picture the iconic Dutch windmill with its four sails turning against a cloudy sky. But the world of traditional mills is far more diverse and fascinating than that single image suggests. Let's explore the remarkable variety of mills that humans have built to harness natural power.
Windmills: Harnessing the Breeze
Windmills appeared in Europe around the 12th century and quickly became essential to communities across the continent. Over the centuries, several distinct types evolved:
Post Mills
The earliest European windmill design, the post mill features an entire wooden body that rotates on a massive central post to face the wind. The miller would push a long tailpole to turn the whole structure. These mills are particularly common in England, Belgium, and northern France.
Tower Mills
Tower mills have a fixed brick or stone tower with only the cap (the top section holding the sails) rotating to catch the wind. This design allowed for larger, more powerful mills and became the dominant form from the 16th century onwards. The Netherlands is famous for its tower mills, many of which were used for land drainage.
Smock Mills
A hybrid design featuring a wooden, weather-boarded body that tapers towards the top (resembling a traditional smock garment), with a rotating cap. Lighter than tower mills, smock mills were popular in England and the Low Countries.
Hollow Post Mills
A variation of the post mill where the main post is hollow, allowing the drive shaft to pass through it directly to machinery at ground level. This design was particularly useful for drainage mills.
Paltrok Mills
Unique to the Netherlands, paltrok mills are essentially smock mills that can rotate entirely on a track, combining features of post mills and smock mills. They were primarily used as sawmills.
Watermills: The Power of Flowing Water
Watermills predate windmills by centuries - the ancient Greeks and Romans used them extensively. The type of waterwheel used depends on the available water supply and terrain:
| Wheel Type | Water Entry | Efficiency | Best For |
|---|---|---|---|
| Overshot | Top of wheel | 80-85% | Hilly terrain with significant head |
| Breast-shot | Mid-height | ~65% | Moderate head available |
| Undershot | Bottom of wheel | 20-30% | Flat landscapes, rivers |
| Pitchback | Back of wheel (top) | ~80% | Specific architectural layouts |
| Horizontal (Norse) | Horizontal flow | ~25% | Simple construction needs |
Did you know? Horizontal "Norse mills" were common in Scandinavia, Scotland, and Ireland. Unlike the familiar vertical wheel, these simple "click mills" used horizontal wheels with the drive shaft going straight up.
Beyond Grain: The Many Uses of Mills
While grinding grain was the most common purpose, mills powered an astonishing variety of industries:
Cutting timber into lumber
Pressing seeds for oil
Beating rags into pulp
Processing wool cloth
Pumping low-lying land
Grinding explosives
Powering bellows & hammers
Spinning and weaving
Finding Mills Today
Thousands of historic mills survive around the world. Some have been preserved as museums, others converted to homes or restaurants, and remarkably, many still work. The Netherlands alone has over 1,000 windmills, while England preserves hundreds of both wind and watermills.
Many working mills welcome visitors and sell stone-ground flour produced the traditional way. There's something magical about watching massive millstones turn, powered by nothing but wind or water, producing flour just as they did centuries ago.
Ready to explore?
Use Mill Index to discover historic mills near you - you might be surprised how many survive in your area.
Browse All MillsMay your sails always catch the wind,
The Mill Index Team