The Netherlands shares borders to the south with Belgium and to the east with Germany, while the North Sea lies to the north and west. Large areas of The Netherlands have been reclaimed from the sea and consequently one-fifth of the country lies below sea level. The country is flat and level and is criss-crossed by rivers and canals. Areas reclaimed from the sea, known as polders, are extremely fertile. The landscape is broken by the forest of Arnhem, the bulb fields in the west, the lakes of the central and northern areas, and coastal dunes that are among the most impressive in Europe.