Flowing entirely in the South Sumatra province, it rises in Barisan Mountains (Bukit Barisan) and meanders slowly eastwards to join the Musi at Kertapati, Palembang.
[2] The Ogan ranks as the third longest river in South Sumatra (behind Musi and Komering).
The river served first as vital transportation artery and communications link.
Formed from thick layers of this river's silt deposits, the Ogan River Valley is one of the most fertile agricultural regions of the province.
The warmest month is October, when the average temperature is around 26 °C, and the coldest is January, at 22 °C.