Oude Maas
The confusing river names are the result of two major flood events, which both resulted in a significant shift in the course and flow of the lower rivers. The first of these events forced the river Meuse (Maas) to take a more northerly course and created a direct connection between the Meuse and the Merwede at the town of Woudrichem. The names of several stretches of the lower rivers were then changed to reflect this, for example the Oude Maas and Nieuwe Maas.