Windmill De Rieker, Amsterdam
Rent a bike and follow the Amstel out of town. In just a short while you'll leave the city proper and find yourself in the 'countryside' where you'll find the 'Windmill De Rieker'.
Built in 1636, it was designed to drain the polders (reclaimed low lying land). This windmill now serves as a family home.
While riding along the Amstel River out of Amsterdam you'll see a couple windmills. This one is further out than the 'Windmill De Rieker' but still an easy bike ride just the same.