The Garrah river rises from the hills of the Kumaon from the Nandhour. It is a tributary of the River Ganga, flows through major industrial areas of Shahjahanpur district of Uttar Pradesh and is one of the major sources for supplying water for life, production, and irrigation especially in the dry season.

The Garrah river flows smoothly southward Khudaganj and the town of Shahjahanpur and after reaching the southern border of the district, it separates the district of Hardoi and then it joins the Ramganga, just above the confluence of the river with the Ganga.

Garrah is one of the most important rivers of Shahjahanpur district.