One of the issues concerning Wawel hill which has not been sufficiently addressed is the outline, construction and the chronology of the early medieval defence embankments. The remains of the wooden, earthen and stone fortifications of early medieval Wawel were discovered in many places on its peripheries. For the first time this happened in the western part of the hill in 1948 (cf. ‘Studies for the Wawel history’ vol.1), and more recently in the years 2000-2006, during archaeological work conducted at the foot of the Thieves’ Tower, over the Dragon’s Den, within the Sandomierz Tower and in the cellars of the old buildings of the seminary, situated in the western part of Wawel. Charred remains of the pillars of the palisade were discovered then, and so were the beams of the wooden chests which stabilised the stone and earthen part of the embankment core.
The dating of these elements remains undecided. At first it was believed that they were built in the 8th c or 9th c., when Wawel was one of the town seats of the Vistulans tribe. Then another hypothesis was presented, that it was built by the Czechs in the middle of the 10th c. and protected the town with the Czech regiment until about 989, when Krakow and the whole of Lesser Poland were overrun by Mieszko I, the prince of Polans. The results of dendrochronological analyses of the wood samples show however that it came from not earlier than 1016. The exact date is additionally complicated by the fact that a stone pre-Romanesque building was erected on the charred ruins of the stone pre-Romanesque building, most probably from the 10th or 11th c. or the beginning of the 12th c. The embankment remained in the form of an earthwork strengthened by a palisade and chest construction, as well as layers of earth with evident traces of the fire.
Another controversial topic in the field of Wawel archaeology is the layering of the remnants of early medieval fortifications, and the recognition of the phases of its construction and use. The most probable thesis is that the layers discovered are the remnants of one embankment. Research conducted in 2003 in the cellars of the Sandomierz Tower produced unexpected results. In two stratigraphic levels remains were discovered of unrelated walls built from vertical beams. Most probably these were remnants of two consecutive embankments - the older one and the newer one, dug into its remnants. The older one consisted of the clay earthwork and palisade, which could have been the primary element of the plaited construction of the inner wall of the embankment, or it could have been a wooden defence curtain with the walkway for the wardens, on its inner side (like in the case of the oldest early medieval fortifications of Krakow suburb, the ‘vicinity’). The older embankment has not been found to bear any traces of violent destruction, at least in the excavation mentioned above. Therefore, it must have been rebuilt. It was used as a base for an oak beam chest framework, filled with earth, sand, clay and stone. It was the basis for the newer embankment, which from the inside of the town was strengthened with a palisade, which repeated the outline of the older structure. The newer embankment was destroyed suddenly during a fire.
Conclusions from the research so far have been confirmed by the results of the latest excavations of the defence embankment, conducted in 2006 in the cellars of the old building of the seminary in the western part of Wawel. These are the first remnants of the two subsequent defence embankments which are so evident.
Detailed information is included in ‘Archaeological Reports’ vol. 47, 1995, vol. 50, 1998, vol. 55, 2003, and vol. 57, 2005.