Why must many Dutch buildings be supported by deep concrete piles?

Many buildings in the Netherlands require deep concrete piles because a significant portion of the country consists of low-lying land, much of which is below sea level.1

This landscape is characterized by polders—reclaimed land often composed of soft, unstable soil layers such as silt and peat. Because these surface layers are too weak to support the weight of heavy structures, builders must drive piles deep into the ground to reach a stronger, more stable bearing stratum. These piles act as columns, transmitting the building's load through the soft, compressible soil to the firmer earth located further underground. In some cases, these concrete piles can reach lengths of up to 65 feet (20 meters).2314