After a 90° change in direction (just north of modern Lorch) the frontier finally took on a more substantial stoney form as the Raetian – Limes, crossing the high plateaux of the Swabian Jura and finally meeting the left bank of the Danube near Eining (Abusina) upstream of Regensburg (Fig. 5). The angular junction between the Upper Germanic – Limes and the Raetian – Limes served to mark the border between Germania superior and Raetia. Whereas the Limes in the Odenwald region was characterized by a timber palisade and separate towers of wood or stone, the 170 km-long Raetian – Limes consisted of a continuous stone wall with integral watchtowers (Fig. 7). This barrier, 1 metre thick and 3 metres high, was often plastered and lime-washed. In later centuries superstitious peasants referred to the time-worn vestiges of the Raetian – Limes as the Devil’s Wall (Teufelsmauer); this did not prevent its structures from being used as a convenient source of building stone.

Fig. 7 – Raetian Limes to the north of the Danube (final form). (© Römerkastell Saalburg)

Two kilometres west of Dalkingen village, where a curve of the Raetian – Limes crowns the hills, is the restored foundation stonework of a triumphal gateway complex (Limestor) with an impressive patterned facade (Fig. 8). The two-metre wide passage through the gatehouse is surprisingly narrow. Many rich finds were made here in 1973-4 and it is believed that this once-impressive structure celebrated a successful and doubtless bloody foray by the Emperor Caracalla into Germania magna against the threatening Alemanni (AD 213).

Fig. 8 – Triumphal gateway in the Raetian Limes (Schwabsberg⇔Dalkingen).

Over the decades, the consolidation of the Limes took place in stages. Initially, in the first century AD, isolated wooden watchtowers and forts and a service road were established. After 120 AD, continuous palisades of stakes became common. By the middle of the second century AD stone watchtowers were replacing wooden watchtowers and stone walls were favoured: the Raetian – Limes is a prime example. As in the case of Hadrian’s Wall in Britannia, a deep ditch (vallum) was usually an essential feature.