ENThe Vilnius Lower Castle was situated in the centre of the city in the northern, western and southwestern parts at the base of the Gediminas hill. It occupied an area of several hectares and was girdled by the Vilnia river. From the end of the 13th century until the beginning of ahe 14th, it was surrounded by a stone defense wall with towers. There was a road on the northern slope of the Gediminas hill between the Lower Castle and the other fortress, that of the Upper Castle located on the summit of the Gediminas hill. The previous studies of this territory were carried out in connection with productive activities: digging ditches for cables, water-supply, sewer pipes and reconstucting the buildings. In March 9, 1988, the Institute of History of the Academy of Sciences was directed to carry out systematic scientific studies of the territory. The aim of the studies was to gather the material for future restoration of the palace. A complex research group consisting of three archaeologists, historians, specialists on art and history of architecture was formed. The archaeological research work was initiated near the still existing parts of the eastern building of the Renaissance palace. One important goal was to gather the information about the cultural layer and the buildings which had been in the territory before the Renaissance palace was erected.