River
Lahn
242 km from source to mouth · Germany.
GermanyFlows into Rhine
In numbers
Length
242km
Average flow
54m³/s
Basin
5,964km²
Drop
221m
from 270 m to 49 m
Country
1
The journey
From source to mouth
242 km of river and 26 stops on the way: 23 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmLahn springat 270 m
- 0 kmObernau-Stausee0.7 km²
- 0 kmNetphen22,972 people
- 10 kmSiegen107,242 people
- 20 kmMudersbach6,358 people
- 21 kmBrachbach2,458 people
- 28 kmKirchen9,342 people
- 30 kmBetzdorf10,560 people
- 30 kmAlsdorf1,765 people
- 34 kmScheuerfeld2,166 people
- 35 kmWallmenroth1,261 people
- 36 kmKatzwinkel2,005 people
- 41 kmMittelhof1,130 people
- 46 kmWissen8,547 people
- 49 kmRoth1,554 people
- 50 kmEtzbach1,289 people
- 52 kmFürthen1,276 people
- 54 kmHamm (Sieg)3,406 people
- 54 kmPracht1,562 people
- 62 kmSiegfall
- 80 kmEitorf19,761 people
- 96 kmHennef (Sieg)48,002 people
- 99 kmWahnbach Reservoir1.6 km²
- 100 kmStoßdorf1,739 people
- 105 kmSankt Augustin56,094 people
- 106 kmSiegburg39,135 people
- 110 kmTroisdorf74,749 people
- 117 kmRhineat 49 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
Right tributary of the Rhine River in Germany
At the mouth it carries 54 m³/s on average: an Olympic pool every 46 seconds. It drops from 270 m to 49 m, 0.9 m per kilometre on average. Its basin covers 5,964 km², about the size of PS. 1.0 million people live in it. Highest water: from December to January. Dams and reservoirs hold back a large share of its water (11% of a year's flow).
Where to start
- SiegenLargest city on its banks · 107,242 people
- Cologne Bonn Airport (CGN)Nearest airport with scheduled flights, 62 km from the cityCar hire at CGN airport (Köln)Discover Cars · Affiliate link↗
- On the water17 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- Kayak and canoe7 put-ins and rapids mapped (OpenStreetMap)
- From May to SeptemberThe best months to visit
Lahn, month by month
Highest water: from December to January
Best months to visit: from May to September.
From about 13 m³/s in the lowest month to 56 m³/s in the highest. An estimate: the monthly flow is modelled from the lowest and highest months of WaterGAP (RiverATLAS, 1971–2000) and the rain and snow along the river (WorldClim). Dams change the real rhythm. The chip is the average air temperature; below it, the month's rain.
Plan the trip
Plan the trip: boat trips, a bed by the river, a car
Some links above are affiliate links: if you book through them we may earn a commission, at no extra cost to you. It never changes what the data on this page says.
The basin
Lahn: the basin in numbers
2,900 km² of land send their water to this river. This is what lives on it.
- 1.0millionpeople live in the basin
- 355/km²people per km²
- 301maverage altitude of the basin
- 866mmof rain a year (basin average)
- 8.5°Caverage air temperature
- 58%protected areas
- 0.2%covered by lakes
- 0.1km³held in reservoirs
What covers the basin
- 68% Forest
- 6% Cropland
- 20% Pasture
- 26% Towns and cities
RiverATLAS (HydroATLAS v1.0, CC BY 4.0): land cover, people, protected areas, glaciers and dams over the whole basin upstream of the mouth.
Along the river
Lahn: what you find on the way
- 30WeirsWehr Neuwiese, Nisterau Dalex, Wehr Schladern and 27 more
- 3Locks
- 2Waterfalls
- 6Rapids
- 1Canoe put-insEitorf-Zentrum Ein-/Ausstieg Nr.10
- 12Boat rampsWindeck-Au Ein-/Ausstieg Nr. 0,, Bootseinsatzstelle Windeck-Schladern, Windeck-Dattenfeld Ein-/Ausstieg Nr.5 and 9 more
- 2Ferry piersSiegfähre
- 1MarinasAm Zehnhoff-Söns
- 3River beachesErholungsbereich Aggerwehr
From OpenStreetMap, within 1.5 km of the river. Not mapped is not the same as not there.
Cross-checked with our atlases
Lahn in our other atlases
What our sister atlases know about the waterfalls on this river, the lakes it flows through, the beaches at its mouth, the mountains where it rises and the islands off its mouth.
1waterfall on the riverCascadyas
2lakes on its wayLakeyas
189mountains at the sourcePeakyas
Waterfalls (1)
On the river, by Cascadyas
- Siegfallkm 62
Cascadyas is coming soonOpen Cascadyas ↗
Lakes and reservoirs (2)
Lakes it flows through, by Lakeyas
- Obernau-Stauseekm 00.7km²
- Wahnbach Reservoirkm 991.6km²
Lakeyas is coming soonOpen Lakeyas ↗
Mountains at the source (189)
Within 15 km of the source, by Peakyas
- Ebschloh8.9 km away686m
- Jagd-Berg2.4 km away676m
- Oberste Henn6.0 km away676m
- Riemen14 km away678m
- Eichholzkopf5.5 km away610m
- Kalteiche13 km away580m
- Pfaffenhain10 km away658m
- Eder-Kopf5.6 km away650m
181 more on PeakyasOpen Peakyas ↗
From space
The source and the mouth, seen from orbit
Sentinel-2 cloudless 2016 by EOX IT Services GmbH (contains modified Copernicus Sentinel data 2016), CC BY 4.0. The glowing line is the river as drawn by RiverATLAS.
Photos
Lahn in pictures
Tributaries
Where it flows, and what flows into it
It flows into
Rhine
The Netherlands1,233 km2,200 m³/sTributaries (26)
Also: Dill, Aar (Lahn), Ohm, Weil, Elbbach, Gelbach, Lumda, Wetschaft, Bieber, Solmsbach, Allna, Emsbach, Ilse, Zwester Ohm, Banfe, Kleebach, Kerkerbach, Perf, Wieseck, Dautphe, Ulmbach, Dörsbach, Mühlbach River, Wahbach
Switzerland
FranceNearby
Rivers nearby
Where these numbers come from
| Name, length, places | Wikidata (Q103148) · CC0 |
|---|---|
| Course, profile, basin | RiverATLAS v1.0 (HydroATLAS, Linke et al. 2019) · CC BY 4.0 — followed along the river network from the point given by Wikidata |
| Flow | WaterGAP (RiverATLAS), 1971–2000 · CC BY 4.0 |
| Climate along the river | WorldClim (RiverATLAS), 1970–2000 · CC BY 4.0 |
| Towns, bridges, dams | Wikidata · CC0; GeoNames · CC BY 4.0 |
| Along the river | © OpenStreetMap contributors · ODbL |
| Images | EOX Sentinel-2 cloudless 2016 · CC BY 4.0; Wikimedia Commons |
| Our other atlases | Cascadyas, Lakeyas, Peakyas — Wikidata · CC0; © OpenStreetMap contributors · ODbL; GeoNames · CC BY 4.0; HydroLAKES · CC BY 4.0; NOAA OISST |
Every source and licence is on the data sources page.
The family
Do you prefer beaches, lakes, mountains, waterfalls, islands, rivers or canyons?
Same idea, other landscapes: field atlases built on open data, month by month, in seven languages.
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