The Canal of Drusus (Fossa Drusiana)

The Fossa Drusiana was the canal between the rivers Rhine and IJssel, dug by Roman soldiers at the end of the first century BCE, when the Roman general Drusus campaigned east and north of the Rhine. The project was probably in some way connected to Drusus' mole at Carvium. The canal still exists as the upper course of the IJssel; two radiocarbon-dates from the oldest deposits of this river suggest that they date back to the beginning of our era.

At the beginning of the canal was the fort of Castra Herculis, which was excavated near Arnhem-Meinerswijk.

A recent interpretation of the evidence points to the fact that the ancient author Suetonius speaks about the canals of Drusus (Claudius, 1), and suggests that a second canal connected Lake Flevo with the Wadden Sea. This makes sense, because if there had been one canal only, the Roman navy would have been force to leave Lake Flevo in the west, at Flevum, and would have had to make a dangerous detour over the open sea. A second canal, leading to the Wadden Sea, would solve this problem.

Geologists have established that at the beginning of our era, the Wadden Sea was indeed connected to what used to be Lake Flevo, but the cause of this breakthrough can not be established.
 

Literature

• Kerst Huisman, "De Drususgrachten: een nieuwe hypothese", in: Westerheem 44 (1995) 188-194.