From 105/110 the river Main, Lat. MOENUS, functioned as river
boundary for a part of the Upper German Limes. The antique name
comes from ancient written sources (Aur. Vict., Caes. 21,2).The
river served not only defensive purposes; it was also an extremely
important transportation route for supplies. The Main was the most
important connection into free Germania for the Roman province
The ancient Main had many bends and meanders, and looked very different from today's regulated river. Fluvial plains varied with narrow break-throughs, as with the Main break-through between Spessart and the Odenwald at the "Mainknie" (Main knee). The Roman complexes of military architecture, forts and watchtowers with civil settlements and cemeteries, lay on the elevated terraces and were protected from flooding.
Geologically, the region is characterised by red sandstone, a material that is still quarried and is easy to work with.
Steidl 2008, 81ff.
Bavarian State Conservation Office – Landesstelle für die nichtstaatlichen Museen & Bavarian State Archaeological Collection with the support of the Bayerische Sparkassenstiftung