Wetzikon–Robenhausen is one of the 111 serial sites of the UNESCO World Heritage Site Prehistoric pile dwellings around the Alps, of which are 56 located in Switzerland. The site is located on Pfäffikersee lakeshore in Robenhausen, a locality of the municipality of Wetzikon in the Canton of Zürich in Switzerland.
Geography The site is located on Pfäffikersee lake shore in Robenhausen, a locality of the municipality of Wetzikon in the Canton of Zürich in Switzerland. The settlement comprises around , and the buffer zone including the lake area comprises around in all.
Description The area at the southern end of the Pfäffikersee lake shore has been inhabited for over 10,000 years. Neolithic hunters and collectors built during the European Mesolithic at various locations storage bins, and in the Neolithic period several small, permanently inhabited settlements near the shore.
Wetzikon–Robenhausen is situated in the Robenhausen wetland between Seegräben and Kempten covering an area of about . The settlement site is characterized by the excellent preservation of organic remains and evidence of textile production, including textiles and parts of a Neolithic loom. A rare find is a board which was probably a door, attributed to the Pfyn culture. The age of a dugout found in 1943 is not yet released. Back to the middle-European Bronze Age era date numerous individual finds, among them two trailers. Further excavations at Tösstalstrasse provided evidence of a settlement of the Glockenbecher culture. Except for individual finds and Jakob Messikommer's excavations to the 1900s, the vast protected area is not yet explored in its entire extent.
Archaeological excavations
The remains of the Neolithic settlements in the protected marsh area were discovered by Jakob Messikommer between 1856 and 1858. On occasion of several excavations Messikommer reported the discovery of a dugout of a peculiar form and other artefacts of the equipment of a hunter; he also distinguished two of a peat layer separate segmented layers which Messikommer interpreted as a settlement that was rebuilt, and in fact he was right. Additional individual finds included longbows, hatchets made of stone and stag horn, and ceramics. Messikommer identified, among the organic finds, however 58 different animal species. In another of his excavations Messikommer revealed the remains of woven fabrics, braids and seeds and evidence of the production of butter. Carved wooden knife, a trowel and scoops, a yoke of hazel, flail, remains of a garment and one from raffia braided mat were other single finds.Pfahlbau Robenhausen, Bericht des Herrn Messikomer. In: Mitteilungen der Antiquarischen Gesellschaft in Zürich, Zürich 1913. Jakob Messikommer's achievements were honored with a memorial stone and the so-called Messikomer Eich, an oak in the Robenhausen reed.
Protection As well as being part of the 56 Swiss sites of the UNESCO World Heritage Site Prehistoric pile dwellings around the Alps, the settlement is also listed in the Swiss inventory of cultural property of national and regional significance as a Class A object of national importance. Hence, the area is provided as a historical site under federal protection, within the meaning of the Swiss Federal Act on the nature and cultural heritage (German: Bundesgesetz über den Natur- und Heimatschutz NHG) of 1 July 1966. Unauthorised researching and purposeful gathering of findings represent a criminal offense according to Art. 24.
Site architecture
The settlement at Robenhausen consisted of rectangular huts, typically measuring about 6 - 7 meters in length with a base area of approximately 40 square meters. Excavations revealed an evolution in building materials: the first and second settlement layers used exclusively softwoods, while the third and final branch utilized split oak wood for floors and stakes.
Pile fastening and foundation
The best preserved remnants of the Robenhausen settlement housing were the piles used to keep the houses elevated from the ground. The logs making up the piles measure from 12 to 18 cm in diameter, having been cut with stone axes. The cut was made clean by the burning of logs, chopping away the chard wood, and repeating. After the logs fell they were then sharpened into 30 cm long point while keeping the bark attached to the upper part of the log. Once these stakes were driven into the lake bed mud, they became almost impossible to pull out because the mud created an airtight seal around the wood.
Longer gable supports were integrated into the pile grid to provide the necessary height for the huts. The walls were then built upon this out of round timber (approximately 4-5cm thick) with a mixture of clay (2-3 cm thick) interspersed with vegetable grains, grass, and straw in a effort to reinforce and insulate the rooms. Gaps were left in the walls, kept as small as possible to preserve heat, used to act as windows, allowing natural light into the building and for smoke to escape.
The foundation of the huts were laid flat with floors. By the area surrounding the hearth, to protect the floor, residents applied a thick layer of clay with sandstone slaps laid flat as a precautionary measure against fire. In the living area a thick layer of moss, beech leaves, and straw acted as padding for sleeping and general comfort away from the work area.
The houses were constructed close to one another, most likely with the roofs touching or connecting. While this did increase the risk of fire spread it also provided mutual protection during periods of cold, strong wings, or snowstorms. Each hut was equipped with its own loom, supplies, and mill, indicating a lack of specialty houses or distinctions among buildings.
Settlement cycles Analysis of the pile foundations indicate that the settlement was completely destroyed by fire at least twice during its long period of existence. These fires most likely spread across the entire settlement area and destroyed the superstructure, and harming the driven piles, of every hut. Dating methods reveal that after the first fire, the village was rebuilt, only to be destroyed by a second fire later. A third, smaller settlement was eventually established on the ruins of the previous two, lasting until the beginning of the Bronze Age.
Clear evidence of this is found in the presence of "replacement piles" directly adjacent to burned ones. Because the fire did not always damage the underground foundation with the same intensity everywhere, parts of the old foundation could sometimes be reused. In the case that this wasn't possible new piles were driven into the lake bed directly next to the old, charred remains, as shown in the image to the right. These new piles were often driven outside the original lines of the previous hut, slightly shifting the footprint of the reconstructed dwellings.
Why the Site was Eventually Abandoned While the residents maintained general upkeep and rebuilt several times after fires, the settlement was eventually abandoned permanently around the beginning of the Bronze Age. Researchers suggest two main reasons:
Peat Formation: Ongoing peat growth made living on the lake increasingly difficult, turning the area into a swamp that was hard to navigate for both residents and visitors. Cultural Shift: The appearance of metal (bronze) may have triggered a change in lifestyle, prompting the population to settle on solid ground rather than continuing the tradition of stilt-house living
Items made of stone, bone, and horn
Only a few rock types from other regions were found, such as Saussurite Gabbro from western Switzerland and Nephrite, which appear only in the third settlement. Stone axes were produced differently from surrounding areas as it seems that residents of Robenhausen focused on stone quality rather than shape, taking durable stones back to the settlement and shaping them with flint tools into their desired form. The axes were crafted with an artistic taste, a narrow and flat side hammered into place with a groove fitted in the stone, it is unlikely that these were tools for everyday use as they were found in pristine condition.
Tools made of horn were used for hoes, cups, and various cutting tools. With few exceptions, stag horn was primarily used, antlers were found at the site but they did not appear to be refined into tools. Tusks and bones were refined into knifes and other tools, for example a harpoon made of deer antler. Bone tools generally appear to have been made with more careful workmanship and with even less volume, not being knapped as the stone tools were but instead carefully cut and carved.
Other weapons, such as spear and arrow heads, were made almost exclusively from flint, the material most valued for producing sharp and durable edges. Flint was also widely used for tools that required cutting ability, including saws and small knives. The bows themselves were carefully carved from yew wood; several longbows made from yew have been found preserved. Hunters likely carried their bows regularly, often accompanied by arrows tipped with flint points; arrowheads made from other materials, such as bone, rock crystal, or nephrite, appear only rarely and were exceptional rather than common.
In addition to the bow and arrows, hunters also relied on other tools. A flint-tipped lance mounted on a long wooden shaft may have been carried as a secondary weapon, useful when prey was encountered at closer range as neither the bow nor the axe alone was sufficient in all situations. Slingstones—small, rounded pebbles typically about 6–8 mm thick—have also been discovered and were probably used with simple slings for hunting small game. These stones were likely gathered from the glacial gravels of nearby streams. The slings themselves were probably made from leather or fur, materials that can not be proved as they rarely survive in the archaeological record. Adhesive substances such as natural pitch or asphalt were also important as they were used to fasten saw blades, arrowheads, and axe heads securely into wooden shafts. Pitch could also serve as a kind of putty for repairing broken pottery handles and other equipment.
A primitive drill press was also discovered at the site. The device consisted of a solid base, such as a board, on which two wooden posts about 40–50 cm in diameter were set vertically about 60–80 cm apart. A lever attached to the top of one post could slide up and down in a slot on the other, allowing pressure to be applied to the drill. On the base was a holding device made of two parallel bars between which the stone or object to be drilled was wedged securely, small cross pieces keeping the drill tube from slipping. The drill itself consisted of a spindle mounted in a rod that ended in a point resting in a small dimple beneath the weighted lever. The lever was pressed down with weight to provide constant downward force and increase friction during drilling. Rotation was produced using a bow whose cord was wrapped around the spindle; the bow was typically about the length of a man’s arm so that each stroke could rotate the drill four or five times. The drill bit was a hollow cylinder made of either wood, bone, or horn, and drilling required abrasive material such as siliceous river sand or crushed quartz sand, which had to be continuously supplied while drilling. Stones were usually roughly shaped by tapping with another stone before drilling, and the final form was achieved by grinding once the hole was completed. The high friction produced by this system also made it effective for starting fires, smoke could appear within about two minutes, and with dry, flammable material it could quickly produce embers.
Fauna and animal husbandry