The metropolitan region comprises approximately one third of the area of Lower Saxony, with almost half the inhabitants of the state.

It has about 3.9 million people in 20 districts and counties with a total of 431 municipalities and is defined by the German Ministerkonferenz für Raumordnung (MKRO) as a medium urban area in Germany.

Hanover is the capital of the state and consists of multiple towns such as Langenhagen, Stadthagen or Garbsen that make up the urban aggomeration.

Factories and industries were placed mostly on the emptier side of the city in order to avoid any risks towards people's health and safety.

The population of Wolfsburg's urban agglomeration is concentrated within the city area but has some parts in the nearby districts Gifhorn and Cremlingen.