the Roman forces left, some simple Pit-houses and wooden frame structures were built. The medieval churches, of which two apses can still be identified, once stood in the southwest corner. Garrison The military unit which occupied Argentovaria in Late Antiquity is unknown. Only the Legio I Martia is documented in the first half of the 4th century as the border protection force responsible for the section on the Upper Rhine. Argentovaria was probably, as usual for the 4th and 5th centuries, occupied by limitanei/ripenses or, more likely during this period, by Germanic Foederati, barbarian allies or mercenaries who were probably part of the army of the Dux Provinciae Sequanicae. One of the most important ancient sources for the disposition of border troops and forts of the 4th and 5th centuries is the Notitia Dignitatum. In it, however, neither the fort name nor the garrison unit or its commanding officer are given. The discovery of a siliqua from the time of Constantius III (408–411), could be a vague indication that it was reoccupied after the devastating invasion of the Vandals and Suebi in 406. Town The town had a small-town character and extended over an area of . At its peak it probably had around 5,000 inhabitants. The distribution of the buildings was, to a large extent, influenced by the topographical considerations. The Rhine valley at that time was characterized by many smaller watercourses and extensive swampy areas. These often prevented coherent development, which is why the houses almost exclusively had to be built on the slightly higher gravel terraces. Some of these could also be reached only by crossing artificially created channels. The town continued to be inhabited even after the military left, under the Flavian emperors in the late first century. The core of the settlement was in the area of the late antique fort. The streets were laid out in a grid. The town had a well-developed infrastructure, which included two baths (thermae), a large public building complex—possibly a mansio, a mithraeum, a harbor on the Rhine, and Gallo-Roman temple district. Many of the houses were decorated with frescos, which testifies to a certain degree of wealth of its citizens. The older foundations were made of basalt, the later ones were laid on a layer of river pebbles. Some areas of the town may have been abandoned as early as the 1st century AD, but some new buildings