Main (river)

The Main (German pronunciation: [ˈmaɪn] (listen)) is the longest tributary of the Rhine. It rises as the White Main in the Fichtel Mountains of northeastern Bavaria[lower-alpha 1] and flows west through central Germany for 525 kilometres (326 mi) to meet the Rhine below Russelsheim, Hesse. The cities of Mainz and Wiesbaden are close to the confluence.

The Main River in Würzburg
Position of the Main in Germany
Physical characteristics
  locationUpper Franconia
  coordinates50°5′11″N 11°23′54″E
  elevation895 metres (at Weissmainquelle)
49°59′40″N 8°17′36″E
Length524.9 km (326.2 mi) [1]
Basin size27,208 km2 (10,505 sq mi) [1]
  average200 m3/s (7,100 cu ft/s)
Basin features
ProgressionRhineNorth Sea

The largest cities on the Main are Frankfurt am Main, Offenbach am Main and Würzburg.[2] It is the longest river lying entirely in Germany (if the Weser-Werra are considered separate).


The Main flows through the north and north-west of the state of Bavaria then across southern Hesse; against the latter it demarcates a third state, Baden-Württemberg, east and west of Wertheim am Main, the northernmost town of that state.

The upper end of its basin opposes that of the Danube where the watershed is recognised by natural biologists, sea salinity studies (and hydrology science more broadly) as the European Watershed.

The Main begins near Kulmbach in Franconia at the joining of its two headstreams, the Red Main (Roter Main) and the White Main (Weißer Main). The Red Main originates in the Franconian Jura mountain range, 50 km (31 mi) in length, and runs through Creussen and Bayreuth. The White Main originates in the mountains of the Fichtelgebirge; it is 41 km (25 mi) long. In its upper and middle section, the Main runs through the valleys of the German Highlands. Its lower section crosses the Lower Main Lowlands (Hanau-Seligenstadt Basin and northern Upper Rhine Plain) to Wiesbaden, where it discharges into the Rhine. Major tributaries of the Main are the Regnitz, the Franconian Saale, the Tauber, and the Nidda.[3]

The name Main originates from Latin Moenis, Moenus or Menus. It is not related to the name of the city Mainz (Latin: Mogontiacum or Moguntiacum).


The Main is navigable for shipping from its mouth at the Rhine close to Mainz for 396 km (246 mi) to Bamberg. Since 1992, the Main has been connected to the Danube via the Rhine-Main-Danube Canal and the highly regulated Altmühl river. The Main has been canalized with 34 large locks (300 × 12 m or 984 × 39 ft) to allow CEMT class V vessels (110 × 11.45 m or 360.9 × 37.6 ft) to navigate the total length of the river. The 16 locks in the adjacent Rhine-Main-Danube Canal and the Danube itself are of the same dimensions.[citation needed]

Weirs and locks

Dams along the Main

There are 34 weirs and locks along the 380 km navigable portion of the Main, from the confluence with the Regnitz near Bamberg, to the Rhine.[4]

  • No.: Number of the lock (from upstream to downstream).
  • Name: Name of the lock.
  • Location: City or town where the lock is located.
  • Year built: Year when the lock was put into operation (replacement dates are also listed where applicable).
  • Main-km: Location on the Main, measured from the 0 km stone in Mainz-Kostheim. The reference point is the center of the lock or lock group.
  • Distance between locks : length in km of impoundment (between adjacent locks).
  • Altitude: height in meters above mean sea level of the upper water at normal levels.
  • Height: Height of the dam in meters (the height of the Kostheim lock depends on the water level of the Rhine).
  • Lock length: Usable length of the lock chamber in meters.
  • Lock width: Usable width of the lock chamber in meters.
No. Name Location Year built Main-km Distance between locks (km) Altitude (m) Height (m) Lock length (m) Lock width (m)
3KnetzgauKnetzgau (Haßfurt)1958359.7817.395219.504.24298.8512.00
8Gerlachshausen mit VolkachVolkach (Schwarzach am Main)1957300.50615.783194.006.30300.0012.00
11MarktbreitMarktbreit (Frickenhausen am Main)1955275.6818.298178.543.31296.4012.00
13RandersackerWürzburg (Randersacker)1950258.88510.143171.833.30299.6012.00
15ErlabrunnErlabrunn (Thüngersheim)1935241.20411.308165.784.15299.2012.00
17HarrbachKarlstadt (Gemünden am Main)1939219.46612.824157.334.90299.4512.00
18SteinbachLohr am Main1939200.67318.793152.435.14299.1012.00
19RothenfelsRothenfels (Marktheidenfeld)1937185.88714.786147.295.26298.4512.00
22FaulbachWertheim (Faulbach)1935147.06513.402133.544.51299.8012.10
23FreudenbergCollenberg (Freudenberg)1934133.94813.117129.034.51300.0012.00
24HeubachGroßheubach (Miltenberg)1932122.36011.588124.524.00300.0012.00
25KlingenbergKlingenberg am Main1930113.0509.310120.524.00300.7112.05
26WallstadtKleinwallstadt (Großwallstadt)1930101.20311.847116.524.00299.9312.00
27ObernauNiedernberg (Aschaffenburg)193092.9098.294112.524.01299.1812.00
28KleinostheimKleinostheim (Stockstadt am Main)1920
29KrotzenburgHainburg (Großkrotzenburg)1920
(formerly Kesselstadt)
Maintal (Mühlheim am Main)1920
31OffenbachFrankfurt am Main (Offenbach am Main)1901
32GriesheimFrankfurt am Main193428.6879.82792.024.49344.05
33EddersheimHattersheim am Main (Kelsterbach)193415.55113.13687.533.61345.46
34KostheimHochheim am Main (Ginsheim-Gustavsburg)1886
(MW Rhine)
Door: 12.00
Chamber: 20.00

Hydroelectric power generation

Most of the weirs or dams along the Main also have turbines for power generation.

  • No.: Number of the dam/weir (from upstream to downstream).
  • Name: Name of the dam/weir.
  • Height: Height of the dam/weir in meters (the height of the Kostheim dam depends on the water level of the Rhine).
  • Power: Maximum power generation capacity in megawatts.
  • Turbines: Type and number of turbines.
  • Operator: Operator of the hydroelectric plant.
No. Name Height (m) Power (MW) Turbines Operator
1Viereth6.006.20Francis(3), Kaplan(1)E.ON Wasserkraft
2Limbach5.363.70Kaplan(2)E.ON Wasserkraft
3Knetzgau4.242.90Kaplan(2)E.ON Wasserkraft
4Ottendorf7.596.30Kaplan(2)E.ON Wasserkraft
5Schweinfurt4.673.80Kaplan(2)E.ON Wasserkraft
6Garstadt4.693.90Kaplan(2)E.ON Wasserkraft
7Wipfeld4.312.90Kaplan(2)E.ON Wasserkraft
8Gerlachshausen mit Volkach6.303.90Kaplan(2)E.ON Wasserkraft
9Dettelbach5.504.20Kaplan(2)E.ON Wasserkraft
10Kitzingen3.663.00Kaplan(2)E.ON Wasserkraft
11Marktbreit3.312.10Kaplan(2)E.ON Wasserkraft
12Goßmannsdorf3.402.00Kaplan(2)E.ON Wasserkraft
13Randersacker3.302.00Kaplan(2)E.ON Wasserkraft
14Würzburg2.750.90Kaplan(3)E.ON Wasserkraft
15Erlabrunn4.152.70Kaplan(1)E.ON Wasserkraft
16Himmelstadt4.302.50Kaplan(1)E.ON Wasserkraft
17Harrbach4.903.00Kaplan(2)E.ON Wasserkraft
18Steinbach5.144.20Kaplan(2)E.ON Wasserkraft
19Rothenfels5.264.20Kaplan(2)E.ON Wasserkraft
20Lengfurt3.992.60E.ON Wasserkraft
21Eichel4.503.10E.ON Wasserkraft
22Faulbach4.514.10E.ON Wasserkraft
23Freudenberg4.514.30E.ON Wasserkraft
24Heubach4.003.40E.ON Wasserkraft
25Klingenberg4.003.00E.ON Wasserkraft
26Wallstadt4.003.40E.ON Wasserkraft
27Obernau4.013.20E.ON Wasserkraft
28Kleinostheim6.809.70E.ON Wasserkraft
30Mühlheim3.774.80E.ON Wasserkraft
31Offenbach3.184.10E.ON Wasserkraft
32Griesheim4.494.90Kaplan(3)Wasser- und Schifffahrtsamt Aschaffenburg
33Eddersheim3.613.84Kaplan(3)Wasser- und Schifffahrtsamt Aschaffenburg
34Kostheim2.364.9Kaplan Pit-Rohrturbinen(2)WKW Staustufe Kostheim/Main GmbH & Co. KG (Gebaut und Betrieben von Stadtwerke Ulm/Neu-Ulm)


The Main and its main tributaries

Tributaries from source to mouth:

Ports and municipalities

Around Frankfurt are several large inland ports. Because the river is rather narrow on many of the upper reaches, navigation with larger vessels and push convoys requires great skill.

The largest cities along the Main are Frankfurt am Main, Offenbach am Main and Würzburg. The Main also passes the following towns: Burgkunstadt, Lichtenfels, Bad Staffelstein, Eltmann, Haßfurt, Schweinfurt, Volkach, Kitzingen, Marktbreit, Ochsenfurt, Karlstadt, Gemünden, Lohr, Marktheidenfeld, Wertheim, Miltenberg, Obernburg, Erlenbach/Main, Aschaffenburg, Seligenstadt, Hainburg, Hanau, Hattersheim, Flörsheim, and Rüsselsheim.

The river has gained enormous importance as a vital part of European "Corridor VII", the inland waterway link from the North Sea to the Black Sea.[5]

Main line

In a historical and political sense, the Main line is referred to as the northern border of Southern Germany, with its predominantly Catholic population. The river roughly marked the southern border of the North German Federation, established in 1867 under Prussian leadership as the predecessor of the German Empire.

The river course also corresponds with the Speyer line isogloss between Central and Upper German dialects, sometimes mocked as Weißwurstäquator.[citation needed]


The Main-Radweg is a major German bicycle path alongside the river. Approximately 600 kilometres long (370 mi), it is the first long-distance instance awarded 5 stars by the General German Bicycle Club (ADFC) in 2008. It starts from Creußen or Bischofsgrün and ends in Mainz.[6]


Notes and references

  1. The Bavarian authorities define the source of the White Main as the source of the Main itself, although the sources of the Red Main and the Franconian Rezat are actually further from the Rhine.
  1. Complete table of the Bavarian Waterbody Register by the Bavarian State Office for the Environment (xls, 10.3 MB)
  2. "Main River | river, Germany". Encyclopedia Britannica. Retrieved 2021-02-04.
  3. Uehlinger, Urs; Wantzen, Karl; Leuven, Rob S.E.W.; Arndt, Hartmut (2009). "The Rhine River Basin". In Tockner, Klement; Uehlinger, Urs; Robinson, Christopher T. (eds.). Rivers of Europe. Academic Press. pp. 238–239. doi:10.1016/B978-0-12-369449-2.00006-0.
  4. "Daten und Fakten" [Facts and figures] (in German). Wasser- und Schifffahrtsdirektion Süd. June 2003. Archived from the original on 13 June 2013. Retrieved 7 June 2009.
  5. "NoorderSoft Waterways Database". Retrieved 2007-10-24.
  6. "Main-Radweg". Archived from the original on 7 November 2019. Retrieved 23 April 2013.


  • Haus der Bayerischen Geschichte (ed.), Main und Meer - Porträt eines Flusses. Exhibition Catalogue to the Bayerische Landesausstellung 2013 (German). WBG. ISBN 978-3-534-00010-4.