Before its conquest by King Prusias I of Bithynia, it was named Cierus or Kieros (Ancient Greek: Κίερος) and belonged to the Heraclea Pontica.

It was an important city on the road between Nicomedia (modern İzmit) at Propontis and Amastris (Amasra) at Euxine in the Pontus region.

Three Roman emperors, Hadrian (r. 117–138), Caracalla (r. 198–217), and Elagabalus (r. 218–222), visited the city in northwestern Asia Minor.

[6][7] Already after the reign of Vespasian (r. 69–79), the city became autonomous in internal affairs and minted its own coins, though it remained dependent to Rome in foreign policy.

In the beginning of the 5th century, the city became part of the newly established late Roman province of Honorias, and after 451 AD, it lost its wealth towards the end of the Byzantine period.

[11][12] In the Ottoman period, the city center was abandoned, and the settlement was called "Üskübü" from σκοπή (skopi) meaning "watchtower".

Another public building in the city, of which the location is not known, is the Domitius bathhouse, mentioned on the honor inscription erected for the son of M. Iulius Cabinius Sacerdos of Prusias.

These walls start right across the ancient bridge located at the edge of the road to Akçakoca, and run as far as Hamam Street.

There are also walls dating back to the Ottoman period on the high parts of the slope where the city was founded.

[12] Coins from the time of Roman emperor Gallienus (r. 253–268) depict the main gate of the city with two towers.

It is a reused grave stele with an ancient Greek inscription dedicated to the mother of a Prusiasan and features a horse relief.

[6][18] A colonnaded street running between the city and the Roman bridge was discovered in 1974 during construction works for an irrigation canal in the southern section of the Düzce-Akçakoca highway D-655.

Some architectural elements, such as the architrave, column fragments, vaulted blocks, and arches are deposited in the Konuralp Museum.

[12] Eleven retaining legs from the old water system of the city, the Kemerkasım Aqueduct, have survived to the present day.

[15] The necropolis of the ancient city, a large, designed cemetery of Roman period with elaborate tomb monuments, is located on three hills in the Şehit Hüseyin Kıl neighborhood of Konuralp.

Artifacts found at this site, such as a garlanded sarcophagus, a Roman period statue, steles, block stones, and earthenware pieces, are exhibited in the Konuralp Museum.

[12] The nearby Konuralp Museum was established in 2003 to preserve the cultural heritage of the ancient city of Prusias ad Hypium.

[15] A statue of Tyche, the presiding tutelary deity, who governed the fortune and prosperity of a city, was uncovered in 1931.

[12] In 2016, another floor mosaic was unearthed inside a villa ruin, dated back to the Roman period of 300–400 AD, at Aynalı village about 3 km (1.9 mi) from the ancient city.