Geography of the European Netherlands European part of the country can be split into two areas: the low and flat lands in the west and north, and the higher lands with minor hills in the east and south. The former, including the reclaimed polders and river deltas, make up about half of its surface area and are less than above sea level, much of it actually below sea level. An extensive range of seawalls and coastal dunes protect the Netherlands from the sea, and levees and dikes along the rivers protect against river flooding. The rest of the country is mostly flat; only in the
Motorways of the Sea land. The routes selected to be Motorways of the Sea should be able to maintain a series of quality criteria; these pertain to frequency, port to port costs, simplicity of administrative tasks. Future routes should compensate for congestion experienced, for example when crossing the Channel (as the similar road networks should do for routes crossing the Alps or the Pyrenees). One envisaged impact of the Motorways of the Sea is energy savings, pollution reductions and more capacity on current overland European transport networks. The adoption of Article 12a of the TEN-T by Council and European Parliament gave a legal framework