From the Wikipedia page [1]
The Burgdorf District (not to be confused with the Burgdorf District in Switzerland) is a former district (Landkreis) in Germany. It existed from 1885 to 1974, when it was absorbed in the Hanover District and subsequently in the Hanover Region. Its area corresponds roughly to the present day municipalities of Wedemark, Isernhagen, Burgwedel, Burgdorf, Uetze, Lehrte and Sehnde.