Argen

The origin of the Untere Argen is the confluence of Börlasbach and Stixnerbach at the western entrance to Missen at about 850 metres (2,790 ft) above sea level in the Allgäu region of Bavaria. From the confluence, it first flows north to Isny im Allgäu, then northwest to Waltershofen, then southwest to Primisweiler. Past Primisweiler, it merges with the Obere Argen.

The main tributaries are the Wengener Argen and the Haslach.

The Federal highway A96 crosses it a number of times.

The Obere Argen originates in a marshy area north-west of Oberstaufen in the Allgäu. It initially flows through the Eistobel gorge, then underneath the Argentobelbrücke, and past Grünenbach towards Wangen im Allgäu. From there it flows on via Neuravensburg to Pflegelberg, where it is united with the Untere Argen.

Lower reaches and mouth and between Kressbronn and Langenargen

Geomorphologically, the Argen has cut a deep and wide valley into the landscape, leading to such place names as Gitzensteig. In some places, the valley is over a kilometre wide. The edges of the valley occasionally rise steeply up to 100 metres (330 ft), and the valley floor is at the level of Lake Constance.

Further down its course, the river bed becomes increasingly broader. The river here flows past the villages of Laimnau, Apflau and Badhütten. In the lower part of its course, the Argen was straightened out considerably. It no longer has oxbow lakes because of the intensive valley agriculture. In recent years the massive concrete walls alongside the river have been replaced with large boulders in most of the shallower zones. Near the estuary at Kressbronn, gravel is mined in larger quantities, creating new lakes along the river.

The ruins of several castles and palaces flank the lower reaches of the Argen: Altsummerau, Neusummerau, the late medieval Gießen Castle at Kreisbrunn, Achberg Castle and Neuravensburg Castle. Remains of an ancient hill fort can be found in the woods above the river.

The mouth into Lake Constance is flanked on both sides by small harbours for pleasure boats. On the left is a camping grounds name Gohren. There is another camping grounds with restaurant at Laimnau. At its mouth, the Argen is 30 metres (98 ft) wide. To prevent flooding, several protective walls have been constructed along the river.

Kayaking is possible; bathing facilities are available.

• Mean lowest water level 1980–2003: 0.29 metres (0.95 ft), 4.87 cubic metres per second (172 cu ft/s)
• Average water level in the years 1980–2003: 0.57 metres (1.9 ft), 20.50 cubic metres per second (724 cu ft/s)
• Historical record levels, flooding on 22 May 1999: 3.58 metres (11.7 ft)