The Gonsbach is a left tributary of the Rhine that winds its way through the districts of Finthen, Gonsenheim, and Mombach. Coming from Finthen, the small stream crosses the allotment gardens and vegetable fields in the lower Gonsbach valley, then flows through the old town center and finally towards Mombach and Mainz Neustadt.

In recent years, the Gonsbach Valley in the Mainz-Gonsenheim district has been renaturalized. Over a length of 1.2 kilometers and an area of six hectares, it has been restored to its original state. Native shrubs and trees such as willows, alders, ash trees, and oaks will be able to grow here again in the future, along with reeds and rushes on the banks. In the future, nature will once again have free rein in the Gonsbach Valley, and the stream will be able to find its way through the area as it pleases.

The Gonsbach Valley landscape conservation area is also set to become a natural habitat again for native animals as part of the renaturation process. Herons, kingfishers, fish in the stream, dragonflies, and amphibians have already been spotted—hopefully many more animals will join them soon. Walkers can find peace and relaxation in the midst of nature on public paths that will continue to run through the Gonsbach Valley in the future.

As is so often the case in Mainz, Roman finds came to light unexpectedly during the ongoing renaturation work. According to scientific findings, the exposed walls are part of a barracks-like building, and an arena-like, circular area was also found. Large stone blocks could also indicate early hydraulic engineering measures. Particularly noteworthy is the artistic depiction of a bound Germanic tribesman on one of the stone blocks.