Pile dwellings

Stilt houses (also called pile dwellings or palafitte) are houses raised on piles over the surface of the soil or a body of water. Stilt houses are built primarily as a protection against flooding, but they also keep out vermin. The shady space under the house can be used for work or storage.

Houses where permafrost is present, in the Arctic, are built on stilts to keep permafrost under them from melting. Permafrost can be up to 70% water. While it is frozen, it provides a stable foundation. If heat radiating from the bottom of a home melts the permafrost, however, the home goes out of level and starts sinking into the ground. Other means of keeping the permafrost from melting are available, but raising the home off the ground on stilts is one of the most effective ways.

In the Neolithic and the Bronze Age, stilt-house settlements were common in the Alpine and Pianura Padana (Terramare) regions. Remains have been found at the Ljubljana Marshes in Slovenia and at the Mondsee and Attersee lakes in Upper Austria, for example. Early archaeologists like Ferdinand Keller thought they formed artificial islands, much like the Irish and Scottish Crannogs, but today it is clear that the majority of settlements were located on the shores of lakes and were only inundated later on. Reconstructed stilt houses are shown in open-air museums in Unteruhldingen and Zürich (Pfahlbauland). In June 2011, the prehistoric pile dwellings in six Alpine states were designated as UNESCO World Heritage Sites. A single Scandinavian pile dwelling, the Alvastra stilt houses, has been excavated in Sweden.

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