European route E31 is an international Class-A road in Europe, part of the United Nations E-road network. It has a north–south reference. It runs from Rotterdam, Netherlands to Ludwigshafen, Germany. Firstly, it leaves Rotterdam, where it links to the E19 and E25 roads. It heads roughly east through the Netherlands, passing through Gorinchem (where it connects to the E311), and Nijmegen before crossing the border into Germany. Its total length is 538 km (334 mi). The route from Parma to La Spezia in Italy, although identified as E33 in the E-network, is also signposted as E31.