River
Osam
314 km from source to mouth · Bulgaria.
BulgariaFlows into Danube2nd longest in Bulgaria
In numbers
Length
314km
Average flow
13m³/s
Basin
2,824km²
Drop
541m
from 562 m to 21 m
Country
1
The journey
From source to mouth
314 km of river and 4 stops on the way: 3 towns and cities on its banks, dams, bridges and the tributaries that feed it.
- 0 kmBalkan Mountainsat 562 m
- 16 kmTroyan21,162 people
- 48 kmLovech26,693 people
- 48 kmCovered Bridge
- 89 kmLetnitsa3,528 people
- 173 kmDanubeat 21 m
Water level along the river (RiverATLAS; the height is exaggerated). Towns: GeoNames and Wikidata; bridges, dams and tributaries: Wikidata.
River in Bulgaria
At the mouth it carries 13 m³/s on average: an Olympic pool every 198 seconds. It drops from 562 m to 21 m, 1.7 m per kilometre on average. Its basin covers 2,824 km², about the size of LU. 141,000 people live in it. Highest water: February. No large dam holds it back: it is one of the world's free-flowing rivers.
Where to start
- LovechLargest city on its banks · 26,693 people
- Sofia Airport (SOF)Nearest airport with scheduled flights, 116 km from the cityCar hire at SOF airport (Sofia)Discover Cars · Affiliate link↗
- On the water1 ferry piers, marinas, boat rentals and boat ramps along the river (OpenStreetMap)
- From May to SeptemberThe best months to visit
Osam, month by month
Highest water: February
Best months to visit: from May to September.
From about 6.8 m³/s in the lowest month to 35 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
Osam: the basin in numbers
2,866 km² of land send their water to this river. This is what lives on it.
- 141,000people live in the basin
- 49/km²people per km²
- 357maverage altitude of the basin
- 612mmof rain a year (basin average)
- 10.2°Caverage air temperature
- 4%protected areas
What covers the basin
- 29% Forest
- 41% Cropland
- 17% Pasture
- 2% 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
Osam: what you find on the way
- 11Weirs
- 1Boat ramps
From OpenStreetMap, within 1.5 km of the river. Not mapped is not the same as not there.
Cross-checked with our atlases
Osam 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.
7mountains at the sourcePeakyas
Mountains at the source (7)
Within 15 km of the source, by Peakyas
- Botev Peak12 km away · prominence 1,567 m2,376m
- Botev vrah11 km away2,376m
- Levski Peak0.1 km away2,166m
- Krastsite4.6 km away2,034m
- Dobrila2.2 km away1,902m
- Kenda Balkan4.2 km away1,307m
- Ravenets9.8 km away
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
Osam in pictures




Tributaries
Where it flows, and what flows into it
It flows into
DanubeNearby
Rivers nearby
Where these numbers come from
| Name, length, places | Wikidata (Q845988) · 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 | 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.