Dia ( grc, Δῖα), also Diospolis (Διόσπολις), was a port city of

ancient Bithynia Bithynia (; Koine Greek: , ''Bithynía'') was an ancient region, kingdom and Roman province in the northwest of Asia Minor (present-day Turkey), adjoining the Sea of Marmara, the Bosporus, and the Black Sea. It bordered Mysia to the southwest, Pa ...

on the

Pontus Euxinus The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Roma ...

Asia Minor Anatolia, tr, Anadolu Yarımadası), and the Anatolian plateau, also known as Asia Minor, is a large peninsula in Western Asia and the westernmost protrusion of the Asian continent. It constitutes the major part of modern-day Turkey. The re ...

Marcian of Heraclea Marcian of Heraclea ( grc-gre, Μαρκιανὸς Ἡρακλεώτης, ''Markianòs Hērakleṓtēs''; la, Marcianus Heracleënsis; fl. century AD) was a minor Greek geographer from Heraclea Pontica in Late Antiquity. His known works are: * ...

places it 60

stadia Stadia may refer to: * One of the plurals of stadium, along with "stadiums" * The plural of stadion, an ancient Greek unit of distance, which equals to 600 Greek feet (''podes''). * Stadia (Caria), a town of ancient Caria, now in Turkey * Stadi ...

east of the mouth of the

Hypius Hypius or Hypios ( grc, Ὕπιος), also Hyppius or Hyppios (Ὕππιος), was a river of ancient Bithynia, not far westward from the Sangarius River. The river itself is very small; but at its mouth it is so broad that the greater part of the ...

, which river is between the

Sangarius River The Sakarya (Sakara River, tr, Sakarya Irmağı; gr, Σαγγάριος, translit=Sangarios; Latin: ''Sangarius'') is the third longest river in Turkey. It runs through the region known in ancient times as Phrygia. It was considered one of th ...

and

Heraclea Pontica __NOTOC__ Heraclea Pontica (; gr, Ἡράκλεια Ποντική, Hērakleia Pontikē), known in Byzantine and later times as Pontoheraclea ( gr, Ποντοηράκλεια, Pontohērakleia), was an ancient city on the coast of Bithynia in Asi ...

. The name in Marcian, Diaspolis (Δίας πόλις), may be a mistake for Diospolis, which

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...

has. There are some very rare coins with the epigraph ''Dias'' (Διας), which Sestini assigns to this place. Its site is located near

Akçakoca Akçakoca is both a town and district of Düzce Province, in the Black Sea region of Turkey, located about 200 km east of Istanbul. The town was named after a Turkish chieftain of the 14th century CE who captured the area for the Ottoman E ...

in Asiatic Turkey.

References

Populated places in Bithynia Former populated places in Turkey History of Düzce Province {{Düzce-geo-stub