Onchestus or Onchestos (), was a

river A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of ...

ancient Thessaly Thessaly or Thessalia (Attic Greek: , ''Thessalía'' or , ''Thettalía'') was one of the traditional regions of Ancient Greece. During the Mycenaean Greece, Mycenaean period, Thessaly was known as Aeolia, a name that continued to be used for one of ...

, flowing near

Scotussa Scotussa or Skotoussa ( or Σκοτοῦσα or Σκοτοτοῦσαι) was a town and polis (city-state) in the region of Pelasgiotis in ancient Thessaly. It was between Pherae and Pharsalus, near the border of Phthiotis, about to the west ...

, through the battlefield of Cynoscephalae into

Lake Boebeis Boebeis Lake (Βοιβηΐς λίμνη, Βοιβία λίμνη, and Βοιβιάς λίμνη) was a lake of Magnesia in ancient Thessaly, mentioned by Homer, and named for the town ( Boebe) on its southeastern shore. The lake is frequently m ...

. It is perhaps the same river as the Onochonus or Onochonos (Ὀνόχωνος), whose waters were exhausted by the army of

Xerxes I Xerxes I ( – August 465 BC), commonly known as Xerxes the Great, was a List of monarchs of Persia, Persian ruler who served as the fourth King of Kings of the Achaemenid Empire, reigning from 486 BC until his assassination in 465 BC. He was ...

during the

Persian Persian may refer to: * People and things from Iran, historically called ''Persia'' in the English language ** Persians, the majority ethnic group in Iran, not to be conflated with the Iranic peoples ** Persian language, an Iranian language of the ...

invasion of

Greece Greece, officially the Hellenic Republic, is a country in Southeast Europe. Located on the southern tip of the Balkan peninsula, it shares land borders with Albania to the northwest, North Macedonia and Bulgaria to the north, and Turkey to th ...

. It is true that

Herodotus Herodotus (; BC) was a Greek historian and geographer from the Greek city of Halicarnassus (now Bodrum, Turkey), under Persian control in the 5th century BC, and a later citizen of Thurii in modern Calabria, Italy. He wrote the '' Histori ...

describes this river as flowing into the

Peneius In Greek mythology, Peneus (; Greek: Πηνειός) was a Thessalian river god, one of the three thousand Rivers, a child of Oceanus and Tethys. Family The nymph Creusa bore him one son, Hypseus, who was King of the Lapiths, and three dau ...

; but in this he was probably mistaken, as its course must have been into Lake Boebeis.

References

Geography of ancient Boeotia Rivers of Greece {{Greece-river-stub