The city located in the northwestern of the Central Anatolia Region, crisscrossed by Porsuk River; has a student city appereance with the presence of Osmangazi and Anatolian Universities. In accordance with the 2019 data of ADNKS (Address based population registration system); total population in the city is 887.475. Eskişehir has a surface area of 13.902 km², located at an altitude of 792 m and continental climate is dominated in a large section of Eskişehir.
Topographic structure of Eskisehir, located at the north-western corner of the Central Anatolia, is formed of the plains in Sakarya and Porsuk River basins and mountains surrounding those basins. The plains have about 26% share in the landforms of the city 22% of which is formed of mountains. The basin plains are enclosed by Bozdag-Sundiken Mountains at north, Turkmen Mountain, Yazılıkaya Plateau and Emirdağ located in the east line of the Central West Anatolian threshold at west and south. Sarısu, Porsuk and Yukarı Sakarya Plains are the most important plains of the province. Porsuk River and Porsuk Dam on this river, Gökçekaya and Yenice Dams on Sakarya River are the most significant water resources of the city.