Balikesir, Turkey is the seventeenth most populous province and the city. The province, which is located in the Southern Marmara Region of the Marmara Region and part of its lands in the Aegean Region, has coast to both the Marmara and Aegean Sea. In Turkey, there are only 6 provinces adjacent to the two seas. The province is located in Northwest Anatolia. There are Bursa and Kütahya provinces in the east, Manisa, and İzmir in the south and Çanakkale in the west. It is adjacent to the Lesbos Island of Greece from Ayvalık district.
Balıkesir takes its name from the old central district that is divided into two today. The old name of the province was Karesi, and it became Balıkesir with the Decree No. 4248 dated October 24, 1926.  There are various rumors about the origin of the word Balıkesir. Roman Emperor Hadrianus took the nickname Adriyanutere because he hunted in a region he owned around the city of Balıkesir. Then he built a castle here again. The name of this castle is known as Paleo Kastro. It is thought that the name of Balıkesir comes from this word. Paleo Kastro means Old Hisar. Some sources say that the word Balıkesir comes from the words Balak Hisar or Balık Hisar. Since the word fish in old Turkish means city, the meaning of the word Balık Hisar is Hisar City. But there are no fortresses or ruins in Balıkesir city center. In addition, there is Hisariçi District in Balıkesir. According to a rumor, it comes from the Persian ruler Honey-Kisra who flocked to the region. According to some sources, it is stated that honey is derived from the word Bal-ı Kesr, which means very, beautiful. According to a new thesis, it is that he came from Bağıkesir. It is confirmed by the Balıkesir Kadi registries and estate records that until the 17th century, viniculture was the most important agricultural activity in the city center.
Researches carried out in many mounds, caves and flat settlements throughout Balıkesir revealed that these lands were settled between 8000 and 3000 BC. 8 km from Havran. Remains from Paleolithic, Neolithic, and Chalcolithic periods were found in İnboğazı caves. During the Babaköy (Başpınar) excavations, the Yortan cemetery, and Kaymak Hill on the Ayvalık Dikili road, copper Age remains and settlements were found. The first city to be mentioned in this region is Agiros (Achiraus). After the collapse of the Anatolian Seljuk State, Karesi Principality was established in the region, and then the region was captured by the Ottoman Empire.