The lower course of the Boorne’s river valley, also called Ouddiep or Koningsdiep, is a real jewel in a crown full of natural beauty. The flawlessness of the river valley is highly regarded according to Dutch standards. Rome, north of Ouddiep at Beetsterzwaag, and the Van Oordt’s Mersken above Terwispel have 3 of the only 30 hectares of blue grassland in the Netherlands. In spring, the former hayfields look exuberantly yellow. This is still the location of the best developed marigold grasslands in Friesland.