 Gernsheim borders in the north on the communities of Biebesheim and Riedstadt, in the east on the town of Pfungstadt and the communities of Bickenbach and Alsbach-Hähnlein (all in Darmstadt-Dieburg), in the south on the town of Bensheim and the communities of Einhausen and Groß-Rohrheim (all in Kreis Bergstraße) and in the west on the community of Hamm (Alzey-Worms).Gernsheim consists of the centres of Allmendfeld, Gernsheim and Klein-Rohrheim.In the first century, there was Roman settlement in what is now Gernsheim.