North of Porta Westfalica

Porta Westfalica

Porta Westfalica is a town in the district of Minden-Lübbecke, in North Rhine-Westphalia, Germany. The name “Porta Westfalica” is Latin and means “gate to Westphalia”. Coming from the north, the gorge is the entry to the region of Westphalia...

 in Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 the River Weser no longer flows through a valley

Valley

In geology, a valley or dale is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys...

, but a broad plain known as the Weser Depression (Weserniederung), consisting of meadows and river terraces.

The depression is accompanied by geest

Geest (topography)

Geest is a type of slightly raised landscape that occurs in the plains of in Northern Germany, the Northern Netherlands and Denmark. It is a landscape of sandy and gravelly soils, usually mantled by a heathland vegetation, comprising glacial deposits left behind after the last ice age during the...

 ridges in places. From Langwedel as far as the River Lesum

Lesum

The Lesum is a 10 km long river in northern Germany, right tributary of the Weser. It is formed at the confluence of the rivers Wümme and Hamme, near Ritterhude, northwest of Bremen. It flows west and flows into the Weser in Bremen-Vegesack....

 it is separated from the Wümme Depression

Wümme Depression

The Wümme Depression is a bog, geest and forest landscape within the Elbe-Weser Triangle in the German state of Lower Saxony. It belongs mainly to the district of Rotenburg. It has no sharply defined boundary with the Lüneburg Heath; as a result many places are seen as belonging to both regions....

 by a narrow ridge of dunes, on which the town of Achim and the older districts of the city of Bremen

Bremen

The City Municipality of Bremen is a Hanseatic city in northwestern Germany. A commercial and industrial city with a major port on the river Weser, Bremen is part of the Bremen-Oldenburg metropolitan area . Bremen is the second most populous city in North Germany and tenth in Germany.Bremen is...

 lie. At many places, such as south of the mouth of the River Aller

River Aller

The River Aller is a small river on Exmoor in Somerset, England.It rises as several small streams around Tivington and Huntscott and flows through the Holnicote Estate past Holnicote and through Allerford, where it passes under a packhorse bridge of medieval origin. It then joins the River Horner,...

 or in Bremen-Huchting the Weser Depression transitions to bog

Bog

A bog, quagmire or mire is a wetland that accumulates acidic peat, a deposit of dead plant material—often mosses or, in Arctic climates, lichens....

 and marsh

Marsh

In geography, a marsh, or morass, is a type of wetland that is subject to frequent or continuous flood. Typically the water is shallow and features grasses, rushes, reeds, typhas, sedges, other herbaceous plants, and moss....

 without any clear boundary. The southern part of the Weser Depression belongs to the state of North Rhine-Westphalia

North Rhine-Westphalia

North Rhine-Westphalia is the most populous state of Germany, with four of the country's ten largest cities. The state was formed in 1946 as a merger of the northern Rhineland and Westphalia, both formerly part of Prussia. Its capital is Düsseldorf. The state is currently run by a coalition of the...

 with its towns of Minden

Minden

Minden is a town of about 83,000 inhabitants in the north-east of North Rhine-Westphalia, Germany. The town extends along both sides of the river Weser. It is the capital of the Kreis of Minden-Lübbecke, which is part of the region of Detmold. Minden is the historic political centre of the...

 and Petershagen

Petershagen

Petershagen is a town in the Minden-Lübbecke district, in North Rhine-Westphalia, Germany.-Geography:Petershagen is situated on the river Weser, approx...

. The borough of Petershagen includes Westphalia's northernmost Weser settlement, Schlüsselburg. North of that the Weser passes the Low Saxon

Lower Saxony

Lower Saxony is a German state situated in north-western Germany and is second in area and fourth in population among the sixteen states of Germany...

 town of Stolzenau

Stolzenau

Stolzenau is a municipality in the district of Nienburg, in Lower Saxony, Germany. It is situated on the left bank of the Weser, approx. 20 km southwest of Nienburg, and 25 km northeast of Minden.-External links:* * by Norman Streat* *...

.

Below Hoya

Hoya

Hoya is a genus of 200-300 species of tropical plants in the family Apocynaceae , fomerly considered to be in the Asclepiadaceae...

 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

Wildeshausen Geest

The Wildeshausen Geest is part of the northwest Germany's geest ridge, that begins near Meppen on the river Ems with the Hümmling, is broken by the Weser depression, continues with the Osterholz Geest and reaches the marshes of Kehdingen by the river Elbe with the ridges of the Wingst and Stade...

 bears away to the west and the Weser Depression broadens to a width of about 20 kilometres (12.4 mi). Here there are also carr

Carr (topography)

A carr is a type of waterlogged, wooded terrain that, typically, represents a succession stage between the original reedy swamp and the eventual formation of forest in a sub-maritime climate....

 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

Schwarme

Schwarme is a municipality in the district of Diepholz, in Lower Saxony, Germany....

 Heath (Schwarmer Heide) and the Thedinghausen Foregeest (Thedinghauser Vorgeest). Downstream of Bremen the marshlands of Stedingen

Stedingen

Stedingen is an area north of Bremen in the delta of the Weser river in north-western Germany.-Founding:In the year 1106, five Dutchmen made a long journey from the mouth of the Rhine to Bremen. They wanted to talk to the Archbishop of Bremen about taking over settling land on the Weser River,...

 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.

The eastern edge of the Weser Depression lies closer to the river from the confluence of the Aller

Aller

The Aller is a river, long, in the states of Saxony-Anhalt and Lower Saxony in Germany. It is a right-hand, and hence eastern, tributary of the River Weser and is also its largest tributary. Its last form the Lower Aller federal waterway...

 near Verden to Bremen-Rönnebeck. In Bremen the Bremen Dunes south of the Lesum separate the Weser Depression from the Wümme Depression. North of the Lesum the Osterholz Geest

Osterholz Geest

The Osterholz Geest is an undulating, sandy area of ground moraine between the city of Bremen and the towns of Bremerhaven and Bremervörde.- Geography :The Osterholz Geest forms the southern part of the Wesermünde Geest....

 near Bremen-Vegesack forms a steep river bank.

In the north, the Weser Depression transitions into the coastal marshes. Northwest of its confluence with the Hunte

Hunte

The Hunte is a 189 km long river in north-western Germany , left tributary of the Weser. It rises in the Wiehengebirge hills. In the Northern German Plain it flows through lake Dümmer. It flows generally northwards through the towns Bad Essen, Diepholz, Wildeshausen and Oldenburg. It flows...

 there are no natural eminences between the Weser and the Jade Bight. The height of this peninsula, comprising Stadland

Stadland

Stadland is a municipality in the district of Wesermarsch, in Lower Saxony, Germany. It is situated on the left bank of the Weser, approx. 32 km northeast of Oldenburg, and 42 km northwest of Bremen. On the west side Stadland bordered to the Jade Bight...

 and Butjadingen

Butjadingen

Butjadingen is a peninsula and municipality in the Wesermarsch districts, in Lower Saxony, Germany.-Geography:Butjadingen is situated on the German North Sea coast. It is bordered on the west and southwest by the Jade River and on the east by the Weser River. It forms the northern part of the...

, lies between 0.8 metres under sea level (NN) and 1.2 metres above it (at a place on the 'neck' of the Jade Bight it reaches 2 metres). The first ridge of geest does not appear until the far side of the Jade Bight, the Friesische Wehde. On the eastern side of the Lower Weser the edge of the Osterholz Geest peels away north of Bremen-Blumenthalto a distance of six to ten kilometres from the river. The marshland here is called Osterstade.

Administrative regions

Politically the Weser Depression is divided between the following administrative units, that belong to the state of Lower Saxony

Lower Saxony

Lower Saxony is a German state situated in north-western Germany and is second in area and fourth in population among the sixteen states of Germany...

 apart from those in the district of Minden-Lübbecke and the city of Bremen:

• Minden-Lübbecke district (North Rhine-Westphalia
  North Rhine-Westphalia
  North Rhine-Westphalia is the most populous state of Germany, with four of the country's ten largest cities. The state was formed in 1946 as a merger of the northern Rhineland and Westphalia, both formerly part of Prussia. Its capital is Düsseldorf. The state is currently run by a coalition of the...
  
  )
• Nienburg district
• Verden district
• Diepholz district
• the town of Delmenhorst
  Delmenhorst
  Delmenhorst is an urban district in Lower Saxony, Germany. It has a population of 74,500 and is located 10 km/6 miles west of downtown Bremen with which it forms a contiguous urban area, whereas the city of Oldenburg is 25 km/15 miles to the northwest. The city has a total area of 62.36 km²...
  
  
• Free Hanseatic City of Bremen
• Wesermarsch district

Source

• LGN = Landesvermessung und Geobasisinformation Niedersachsen: Regionalkarten 1:100 000, Nr.10 "Mittelweser" und Nr.2 "Nordoldenburg".