Chronologia i stratygraa wykopu w rejonie przyczółka mostu zachodniego na podgrodziu (badania w latach 60. XX wieku)

The present paper discusses the results of excavations carried out within the framework of the so-called “Millennium research” (1961–1962) at Ostrów Lednicki. A survey of the abutment of the western (Poznań) bridge allowed to define the time of construction of the bridge as the beginning of the second half of the 10th c. This chronology was confirmed by the dendrochronological analysis of piles. These dates define the time of construction of the bridge as 963–964, while its repairs were carried out in 981, 995, 1007–1008, 1015–1018, 1022 and 1033. These dates imply that repairs of the bridge were carried out at even intervals, each 12–14 years. This may have resulted from the natural durability of the wood used for the construction of the bridge. A stone pavement was discovered around the abutment of the bridge. It hardened the entrance to the bridge. There were also c. 2.5 m wide roads near the lake, which went southwards from the bridge to the stronghold and northwards to the suburbium. The latest date of 1033 would suggest the last repair of the bridge. An assemblage of pottery from layers associated with the destruction (burning) of the bridge is dated to the mid-11th c. The latest of the received dates and the assemblage of pottery from burnt layers allow for dating of the destruction of the Poznań bridge to the mid-11Th c. The bridge was probably burnt in the course of fights over the island. This is implied by finds from the abutment: a sword and a spur, as well as by numerous militaria extracted from the lake by underwater archaeologists: a helmet, a chainmail, swords, stirrups, spurs, spearheads and axes. The lack of an evident burnt layer (apart from scorched beams) and a thick level of rubble may imply that the fire did not destroy the bridge completely and the structure did not collapse at once. The bridge, not repaired and not in use after the fire, underwent slow decomposition. From then, a depression of the terrain near the lake was not used for building purposes and the remains of the bridge and the road were covered by naturally growing layers of loam, sand and turf humus. From the mid-11th c. the island was connected to the land by a ferry crossing, built in the place of the eastern (Gniezno) bridge. In this location, the distance from the island to the mainland is half as much (c. 200 m) as on the western side.