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Sakarya is a fairly old city, which dates back to 8^th century BCE. First to arrive   were the Phrygians, Lydians, and Persians but Sakarya got its ancient identity from its Romans and Byzantine rulers, which is evident once you begin to travel around. One of the most important remains of historical significance is the Justinian Bridge (Beş Köprü), built by the Byzantine Emperor Justinian between 527 and 565 and is well worth seeing. Some of the other important historical  attractions of the city are Orhan Mosque (Orhan Cami) , Uzun Bazaar (Uzun Çarşı), Sakarya Museum (Sakarya Müzesi), Rahime Sultan Mosque (Rahime Sultan Cami), Rüstem Paşa Mosque (Rüstem Paşa Cami), Kuvayi Milliye Museum (Kuvayi Milliye Müzesi), Seyifler Castle (Seyifler Kalesi), Harmantepe Castle (Harmantepe Kalesi), Paşalar Castle (Paşalar Kalesi), Elvan Bey Almshouse (Elvan Bey İmarethanesi), Çakırlar Mansion (Çakırlar Konağı) and Hisar Mansion (Hisar Konağı).

Justinian’s Bridge (Beş Köprü)

Justinian Bridge (Justinianus Köprüsü), built on Çark River (Melas Çayı), which drains the waters of Sapanca Lake (Sapanca Gölü) into Sakarya River, is one of the most magnificent structures in Anatolia of the Early Byzantine Period. Built by Justinian (527-565), this stone bridge is 365 meters long, 9.85 meters wide and has a total of 12 arches. Previously called "pons" (bridge) in Latin, the bridge did not have a specific name. Later, people who did not know that "pons" meant "bridge" in Latin perceived this word as a proper name and called the bridge as Pontogephyra meaning "Bridge of Pons". Later, this name turned into Pentegephyra (Five Bridges), but the bridge is neither five-piece nor five-arched in one form or another. Justinian’s Bridge was included in the UNESCO Tentative List of World Heritage in 2018. 

Orhan Mosque 

Orhan Mosque (Orhan Cami) was built by Konuralp Bey in the name of Orhan Gazi. The mosque, made of ashlar blocks, has no dome, a single minaret and a rectangular plan. It was completely renovated during the Sultan II. Abdülhamit’s reign. This mosque is a nice place for a short break in the hustle and bustle of daily life, with the Uzun Bazaar (Uzun Çarşı) right next to it, and places where people can shop, drink Turkish tea and eat simit.

Uzun Bazaar

It is located next to the Orhan Mosque (Orhan Cami), consists of about 100 shops and is one of the oldest and most established bazaars in the city from the Ottoman period. It is the main commercial center of the city and a very important shopping place for those who live in Sakarya and those who visit the city.

Sakarya Museum

In the garden of the museum, architectural pieces, tombstones, altars, inscribed stones, ossuaries, terracotta food jars and column bases belonging to the Roman and Byzantine periods are displayed. In the exhibition hall of the museum, archaeological artifacts from prehistoric times, Roman and Byzantine periods and ethnographic artifacts belonging to the Ottoman and Republican periods are exhibited. Archaeological artifacts include flat hand axes, terracotta pots, fragrance and perfume bottles, metal and glass artifacts. Among the ethnographic works, the goods used by Mustafa Kemal Atatürk, firearms and cutting weapons, copper pots, seals and handicrafts from the Ottoman and Republic periods are exhibited.