Until well into the 16th century, the area of the present-day Zwinger complex was still outside the city fortifications. Close by ran an old stretch of the River Weißeritz that no longer exists, which emptied into the Elbe by the Old Castle. In 1569, major work began on redevelopment and new buildings by the fortifications west of the castle based on plans by master builder, Rochus Quirin, Count of Lynar, who came from Florence.