The
Osam is a river in northern
BulgariaBulgaria , officially the Republic of Bulgaria , is a country in the Balkans in south-eastern Europe. Bulgaria borders five other countries: Romania to the north , Serbia and the Republic of Macedonia to the west, and Greece and Turkey to the south...
. Its
drainage basinA drainage basin is an extent of land where water from rain or snow melt drains downhill into a body of water, such as a river, lake, reservoir, estuary, wetland, sea or ocean...
is in between that of the river
VitThe Vit also Vid is a river in central northern Bulgaria with a length of 189 km. It is a tributary of Danube. The source of the Vit is in Stara Planina, below Vezhen Peak at an altitude of 2,030 m, and it empties into the Danube close to Somovit...
to the west and the
YantraYantra are 'instruments'. The meaning is contextual. Much like the word 'instrument' itself. It can stand for symbols, processes, automata, machinery or anything that has structure and organization. One use popular in the west is as symbols or geometric figures. Traditionally such symbols are used...
system to the east. The river has two main tributaries in its upper course: the Black Osam takes its source from the foot of
Levski PeakLevski Peak is a peak in the central Balkan Mountains, in Lovech Province, Bulgaria. It is named after the famous Bulgarian revolutionary Vasil Levski. The peak is high and is situated on the main ridge of the mountain range to the west of Golyam Kupen Peak.The peak is more famous with its old...
in the
Balkan MountainsThe Balkan mountain range is a mountain range in the eastern part of the Balkan Peninsula. The Balkan range runs 560 km from the Vrashka Chuka Peak on the border between Bulgaria and eastern Serbia eastward through central Bulgaria to Cape Emine on the Black Sea. The highest peaks of the Stara...
, at an altitude of , while the White Osam has its source on the northern slopes of the Kozya Stena peak. In
TroyanTroyan is a town in central Bulgaria with population of about 30,000 and territory of 888,850 m². It is located 160km from Sofia. The nearest civilian airport is Gorna Oryahovitsa, 105 km away...
, the black and white Osam join. It runs north towards
LovechLovech is a town in north-central Bulgaria with a population of about 50,000. Lovech is the administrative centre of Lovech Province and of the subordinate Lovech municipality, and is located 150 km from the capital city of Sofia...
, then north-east until
LetnitsaLetnitsa is a town in central northern Bulgaria, part of Lovech Province. It is the administrative centre of Letnitsa municipality and lies in the northeastern part of the province, close to the town of Levski.-Municipality:Letnitsa municipality includes the following four places:* Gorsko Slivovo*...
and
LevskiLevski is a town in central northern Bulgaria, the administrative center of Levski Municipality in the very southeast of Pleven Province. It is located in the valley of the Osam River and was called Karağaç during the Ottoman rule of Bulgaria and until 1897, when it was renamed after the...
, where it turns north-west until it flows into the river
DanubeThe Danube is the longest river in the European Union and Europe's second longest river after the Volga.The river originates in the Black Forest in Germany as the much smaller Brigach and Breg rivers which join at the German town Donaueschingen, after which it is known as the Danube and flows...
5 km west of the town of
NikopolNikopol is a town in northern Bulgaria, the administrative center of Nikopol municipality, part of Pleven Province, on the right bank of the Danube river, 4 km downstream from the mouth of the Osam river...
. The ancient name of the river was
Assamus.