The Nesselberg is a ridge up to 378.2 m above sea level (NN) high in the Calenberg Highland which, together with the Kleiner Deister and the Osterwald, forms a group of three contiguous hill regions in the northwestern part of the Leine Uplands. It lies between Altenhagen I and Coppenbrügge in Lower Saxony, Germany.
The Nesselberg is located more or less north of Coppenbrügge, immediately south of the Kleiner Deister and nordwest of the Osterwald. It lies north of the Gelbbach valley, through which state road no. 422 runs from Eldagsen to Coppenbrügge. Immediately east of this valley is the Osterwald. The border between Hanover region and the district of Hameln-Pyrmont runs along the crest of the Nesselberg.
On the saddle between the Nesselberg and Kleine Deister, and therefore between the Wolfsköpfen to the northeast and the Grasberg to the southwest, stands the old Wolfsbuche (today a car park for walkers); the Schwarze Bach ("Black Brook"), a tributary of the Gehlenbach rises here. Both ridges lies within the borough of Springe, the Springe municipalities of Altenhagen I and Eldagsen as well as the Brünnighausen and Dörpe in the municipality of Coppenbrügge.
Over the crest of the Nesselberg runs part of the sandstone wall known as the Saupark Springe which is around 16 km long and 2 m high and which runs for a long way over the Kleiner Deister. Part of the Roswithaweg footpath also runs from north to south over the Nesselberg and the neighbouring Kleiner Deister; this is a long-distance hiking trail from Nienburg/Weser to Bad Gandersheim.