| Mert River | |
|---|---|
River mouth at Samsun | |
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The River Mert (Turkish: Mert Irmağı or Merd Irmağı); anciently, the Lycastus (Ancient Greek: Λύκαστος, romanized: Lykastos) is a river in Turkey which flows into the Black Sea at Samsun.
In 2022 flow measurements were lacking.

The ancient town of Lycastus in Pontus was located on the river; the site has not been located.
A local politician claims the river suffers from domestic and industrial pollution, and fish die off in 2014 is being investigated by local officials.
In 2012 flooding killed 5 people.[citation needed]
B3. Name: Lykastos fl. Modern Name / Location: Merd Irmağı. Reference: Olshausen 1984, 146., with accompanying Map-by-Map Directory.