From the World Heritage inscription:
The Beemster Polder, dating from the early 17th century, is the oldest area of reclaimed land in the Netherlands. It has preserved intact its well-ordered landscape of fields, roads, canals, dykes and settlements, laid out in accordance with classical and Renaissance planning principles.
Visit the Beemster Polder was like visiting Wisconsin….except flatter. The area is mostly dairy farms and it is typical of the polders (reclaimed land) which makes up much of the Netherlands. It totally explains Wisconsin is a dairy state.