Bordered in the north by the forested ridges of the Bückeberg and the Deister, the nature park covers almost 1000 sqkm from the eastern Weser Hills, Harrl and Süntel running along both sides of the River Weser southwards to the Ith ridge, the Osterwald and the Thüster Berg, through a very varied landscape of wooded, rolling hills and small valleys with a myriad streams and rivers.