Weser Depression

The Weser Depression (German: Weserniederung) or Weser Lowlands is the region north of Porta Westfalica in Germany, where the River Weser no longer flows through a valley, but a broad plain consisting of meadows and river terraces.

The flat plain of the depression is interrupted by geest ridges in places. From Langwedel, as far as the River Lesum, it is separated from the Wümme Depression by a narrow ridge of dunes, on which the town of Achim and the older districts of the city of Bremen lie. At many places, such as south of the mouth of the River Aller or in Bremen-Huchting, the Weser Depression transitions to bog and marsh without any clear boundary. The southern part of the Weser Depression belongs to the state of North Rhine-Westphalia, with its towns of Minden and Petershagen. The borough of Petershagen includes Westphalia's northernmost Weser settlement, Schlüsselburg. North of that, the Weser passes the Low Saxon town of Stolzenau.

Below Hoya, the Weser reaches the Breslau-Magdeburg-Bremen glacial valley, which approaches from the southeast. As the Weser heads off in a northwestern direction, the edge of the Wildeshausen Geest bears away to the west and the Weser Depression broadens to a width of about 20 kilometres (12 mi). Here there are also carr landscapes. From Achim to Bremen-Blumenthal, the width of the depression reduces again to about 10 kilometres (6.2 mi). In the wide sections of the depression the soil does not just consist of river sediments or bog, but is also sandy in places. These areas of sand at the level of the depression are also known as 'foregeest' (Vorgeest), but are nevertheless separated by a boggy strip from the ascending edge of the geest itself. The largest are the Schwarme Heath (Schwarmer Heide) and the Thedinghausen Foregeest (Thedinghauser Vorgeest). Downstream of Bremen, the marshlands of Stedingen come close to the Weser. The river is separated from the northwestern edge of the geest by a wide, nowadays largely cultivated, strip of moor.

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