How to get there: Those coming from Istanbul using the D-100 or TEM highway should take the Gölyaka exit, and those coming from Ankara should take the Kaynaşlı exit to reach Düzce city center, and then continue 6 kilometers towards Konuralp.
The ancient city of Prusias ad Hypium, located in the Konuralp neighborhood of Düzce, dates back to the 3rd century BC. Konuralp first appeared on the historical stage under the name Hypios. Built on a hill that stretches from east to west, near the Küçük Melen and Tabak Rivers, and ending in the plain, the town's name later became Kieros. The Bithynians, who launched an offensive against the Mariandynians and the Herekleia Kingdom, conquered Kieros, east of the Sangarios River, under the leadership of their king, Prusias I (230-182 BC). Prusias I established a Bithynian colony there, quickly making the city more prosperous than before. He adorned the city with many monuments, fortified it, and changed its name. Thus, Kieros disappeared from the historical scene at the end of the 2nd century BC, and the city took the name "Prusias" in honor of the king.
The Ancient Theatre, known popularly as the Forty Steps Theatre, was built in the Hellenistic period (300-30 BC). Its additions date from the Roman period (30 BC-300 AD). Located in the ancient city of Prusias ad Hypium, the theatre, which has two levels, has only its backstage wall and a section of the seating rows of the second level remaining today.
The Kemerkasım Aqueducts; 11 buttresses from the city's old water system have survived to the present day. The aqueduct, believed to have carried water channels, is constructed of rubble stone.
The Horse Gate; a Group I monument, the Horse Gate and its extensions, are the entrance gate to the ancient city of Prusias ad Hypium. Inscribed repurposed materials were used in the wall repairs during different periods. The gate lintel, with its horse relief, is made of local limestone. A tomb stele, commissioned by a Prusias resident for his mother, is located on the lintel, featuring a depiction of a horse and a Greek inscription.
The Roman Bridge; the bridge dates from the Roman period. Its current dimensions are 4.80x30.25x3.17 meters, while its actual dimensions were 4.80x39.20x3.17 meters. Its distinguishing feature is that it was constructed by joining white marble blocks together without the use of mortar.
The Western City Walls are 4.70 meters high and 118 meters long. At the western end of the wall, there is an entrance built with repurposed block stones. Cut block stones were used in the walls and they were constructed without mortar. While the city walls date back to the Hellenistic and Roman periods, during repairs in the Eastern Roman period, repurposed blocks were used in the construction of the city walls and other architectural fragments. The Konuralp Museum, established to preserve the rich cultural heritage of the ancient city of Prusias ad Hypium, opened to the public in 2003. It consists of 3 exhibition halls, 1 laboratory, 2 storage rooms, 1 conference hall, and administrative sections. The museum houses a total of 6,237 artifacts, including 1,848 archaeological items, 491 ethnographic items, and 3,898 coins.
