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
Delta Works future demands. The latest upgrades are made under the High Water Protection Program. During the execution of the works, changes were made in response to public pressure. In the Nieuwe Waterweg, the heightening and the associated widening of the dikes proved very difficult because of public opposition to the planned destruction of important historic buildings to achieve this. The plan was changed to the construction of a storm surge barrier (the Maeslantkering) and dikes were only partly built up. The Delta Plan originally intended to create a large freshwater lake, the "" (Zeeland Lake). This would have caused major environmental