The county is located to the south of Marmara Sea and west of Iznik Lake and it is 45 km to Bursa City. Situated on Bursa-Yalova Road, the county is surrounded by Samanlı Mountains in the North and Katırlı Mountains in the South. The economy is based on advanced agriculture and industry. According to Ilıpınar Mound excavations, the history of Orhangazi reaches back to 5200 BC, which makes it one of the oldest settlements in Anatolia. The county which was known as Basilinopolis during the Roman period was conquered by the Ottoman sultan Orhan Gazi in the 1330’s and was finally named Orhangazi in 1913. Apart from all this, the most delicious olives in the world are grown here, climatically affected by Keramet Hot Springs, on the western shore of Lake Iznik.