The pile dwelling of laghetto della Costa occupied the South West lakeside, as it aws highlighted by the archeological excavations carried out in the years 1885-1886, 1901, and 1909 by Federico cordenons, and in 1906 by alfonso Alfonsi. The great majority of archaeological finds( mainly pottery, bone and antler artifacts and stone tools) is kept in the collections of the National Archaeological Museum in Este and the Civic Archaelogical Museum in Padua. Such finds prove the long lasting of settlement, from the final part of the Copper Age to the beginning of the Late Bronze Age. The bowls on support corded decoration date back to the first stage of th site. The more rappresented stages, however, are those dating back to Early and Middle Bronze Age, between XXIII and XV century b.C. Several small jugs with egg-shaped or trunk-conical profiles made of coarse black ceramic, and bone and antler artifacts date back to that period. The village lied along the South-West shoreline, and it was perhaps divided into more settlement zones, with pile-dwellings constructions mainly of the type “su bonuifica” described by the excavators as made up of structures with big horizontal oak-wook beams. The beams were coupled one another and supported by piles dug into the lake mud, and the structures filled up with different size branches and big stones. The floors were made of wood planking where the hearts stood isolated from the floor through a slab basement. In the area of excavation carried out by A. Alfonsi adouble aligment of piles was discovered; such piles were dug into lake mud at a regular distance with no bearing funtion, just definig the village. The preservation of one of the smal piles, which was found at the side of a planking floor and still kept in the Civic Museum of Padua, has allowed to obtain a radiocarbon date of 3675+- 29 years BP, so dating of the structure betwenn XXII and XX centuries b. C. (2133 -1983 cal BC)
The importance of Costa Lake as a cultural/natural landscape is recognised internationally, having included in the transnational serial UNESCO Cultural site 'Prehistoric pile dwelling sites in the Alps' designated in 2011.
Photo: Comune di Arquà Petrarca.