Limes Germanicus connects with Danubian Limes
Augustus
The first emperor who began to build fortifications along the border was Augustus, shortly after the devastating Roman defeat at the Battle of the Teutoburg Forest in 9 AD. Originally there were numerous Limes walls, which were then connected to form the Upper Germanic Limes along the Rhine and the Rhaetian Limes along the Danube. Later these two walls were linked to form a common borderline.