River
Alster
56 km from source to mouth · Germany.
GermanyFlows into Norderelbe
In numbers
Length
56km
Average flow
870m³/s
Basin
581km²
Drop
22m
from 21 m to -1 m
Country
1
The journey
From source to mouth
56 km of river and 63 stops on the way: 48 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmHenstedt-Ulzburgat 21 m
- 1 kmKayhude1,192 people
- 2 kmHeidkruger Alsterschleuse
- 4 kmTangstedt5,937 people
- 10 kmDuvenstedt6,022 people
- 12 kmWohldorf-Ohlstedt4,450 people
- 12 kmLemsahl-Mellingstedt6,554 people
- 15 kmBergstedt9,845 people
- 18 kmSasel24,457 people
- 19 kmPoppenbüttel24,135 people
- 19 kmPoppenbüttler Schleuse
- 19 kmBäckerbrücke
- 20 kmGrevenaubrücke
- 21 kmWellingsbüttel10,935 people
- 24 kmHummelsbüttel17,365 people
- 27 kmFuhlsbüttel13,348 people
- 27 kmOhlsdorf14,942 people
- 28 kmSteilshoop19,343 people
- 29 kmBarmbek-Nord40,261 people
- 30 kmHindenburgbrücke
- 31 kmDammbrücke
- 32 kmGroß Borstel9,642 people
- 33 kmNiendorf40,906 people
- 34 kmAlsterdorf13,271 people
- 35 kmEppendorf24,806 people
- 35 kmWinterhuder Brücke
- 35 kmHamburg-Nord315,514 people
- 35 kmWinterhude56,382 people
- 36 kmGoernebrücke
- 36 kmWarburg Haus, Hamburg
- 36 kmHoheluft-Ost23,116 people
- 37 kmHoheluft-West13,435 people
- 37 kmHarvestehude17,666 people
- 37 kmEimsbüttel269,118 people
- 37 kmKrugkoppelbrücke
- 38 kmBarmbek-Süd35,880 people
- 38 kmWandsetributary
- 39 kmEilbek22,235 people
- 40 kmHamm37,989 people
- 40 kmBorgfelde7,099 people
- 41 kmSt. Georg11,349 people
- 41 kmBinnenalster1.6 km²
- 41 kmHamburger Kunsthalle
- 41 kmLombard Bridge
- 41 kmHammerbrook5,069 people
- 41 kmHamburg-Mitte301,231 people
- 41 kmHamburg-Altstadt2,257 people
- 41 kmRothenburgsort9,043 people
- 42 kmRotherbaum17,114 people
- 42 kmHamburg1,973,896 people
- 43 kmNeustadt12,657 people
- 43 kmSternschanze7,965 people
- 43 kmPulverturmsbrücke
- 44 kmHafenCity5,803 people
- 44 kmKleiner Grasbrook1,120 people
- 46 kmSt. Pauli21,902 people
- 47 kmAltona-Altstadt29,455 people
- 48 kmAltona-Nord25,802 people
- 50 kmAltona250,192 people
- 51 kmOttensen35,136 people
- 54 kmOthmarschen16,009 people
- 55 kmGroß Flottbek11,076 people
- 56 kmNienstedten7,114 people
- 56 kmFinkenwerder11,702 people
- 56 kmNorderelbeat -1 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
Right tributary of the Elbe in Schleswig-Holstein and Hamburg
At the mouth it carries 873 m³/s on average: an Olympic pool every 2.9 seconds. It drops from 21 m to -1 m, 0.4 m per kilometre on average. Its basin covers 581 km². 22.2 million people live in it. Highest water: from February to March and December. Dams and reservoirs hold back a large share of its water (13% of a year's flow).
Where to start
- HamburgLargest city on its banks · 1,973,896 people
- Hamburg Helmut Schmidt Airport (HAM)Nearest airport with scheduled flights, 9 km from the cityCar hire at HAM airport (Hamburg)Discover Cars · Affiliate link↗
- On the water101 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- Kayak and canoe5 put-ins and rapids mapped (OpenStreetMap)
- From May to SeptemberThe best months to visit
Alster, month by month
Highest water: from February to March and December
Best months to visit: from May to September.
From about 470 m³/s in the lowest month to 1,600 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
Alster: the basin in numbers
138,382 km² of land send their water to this river. This is what lives on it.
- 22.2millionpeople live in the basin
- 163/km²people per km²
- 278maverage altitude of the basin
- 619mmof rain a year (basin average)
- 8.0°Caverage air temperature
- 28%protected areas
- 1.0%covered by lakes
- 3.5km³held in reservoirs
What covers the basin
- 30% Forest
- 38% Cropland
- 11% Pasture
- 7% 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
Alster: what you find on the way
- 25WeirsSandfelder Schleuse, Rader Schleuse, Wohldorfer Schleuse and 22 more
- 13LocksBrandshofer Schleuse, Schleusenkanal, Mühlenschleuse and 10 more
- 6Waterfalls
- 5Canoe put-insAnleger Alter Güterbahnhof, Anleger Ballindamm and 3 more
- 26Boat rampsKanu Umtragehilfe and 25 more
- 32Ferry piersWinterhuder Fährhaus, Streekbrücke, Krugkoppelbrücke and 29 more
- 24MarinasBobby Reich, Alster-Jugend-Segelclub e.V., Norddeutscher Regatta Verein and 21 more
- 3River beachesPferdeschwemme, El Ray Beach Club, Övelgönne
From OpenStreetMap, within 2.5 km of the river. Not mapped is not the same as not there.
Cross-checked with our atlases
Alster 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.
1lake on its wayLakeyas
7mountains at the sourcePeakyas
2islands off the mouthIslandyas
Lakes and reservoirs (1)
Lakes it flows through, by Lakeyas
- Binnenalsterkm 281.6km²
Lakeyas is coming soonOpen Lakeyas ↗
Mountains at the source (7)
Within 15 km of the source, by Peakyas
- Schüberg14 km away63m
- Müllberg Hummelsbüttel10 km away79m
- Winser Berg7.9 km away
- Katten Berg9.6 km away
- Buns-Berg14 km away
- Lieth-Berg9.6 km away
- Rathkrügen6.2 km away
Islands off the mouth (2)
Within 30 km of the mouth, by Islandyas
- Finkenwerder1.5 km away
- Julssand21 km away
Islandyas is coming soonOpen Islandyas ↗
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
Alster in pictures
Tributaries
Where it flows, and what flows into it
Tributaries (16)
Also: Tarpenbek, Wandse, Osterbek, Saselbek, Rodenbek, Bredenbek, Ammersbek, Diekbek, Höllenbek, Minsbek, Wischbek, Wöddelbek, Mellingbek, Rönne, Horstbek, Sielbeck
CzechiaNearby
Rivers nearby
Where these numbers come from
| Name, length, places | Wikidata (Q1219) · CC0 |
|---|---|
| Course, profile, basin | RiverATLAS v1.0 (HydroATLAS, Linke et al. 2019) · CC BY 4.0 — followed from the source to the mouth 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 | Lakeyas, Peakyas, Islandyas — 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.
beaches
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Every summit in 3D: summit weather, the 0 °C line, huts and trails.Visit 
waterfalls
Every waterfall: height, flow month by month and when it roars.Coming soonVisit islands
Every island from the sea up: size, sea temperature, ferries and 3D.Coming soonVisit 
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Every river from source to sea: the journey, the flow and the basin in numbers.You are here
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Every canyon cut to scale: depth to the floor, rim and floor temperatures, trails and viewpoints.Coming soonVisit