The Geography of the Puranas c11.s1.12

c11.s1.12

Magadha. Further east of the Kāśi-Kosala janapadas beyond the Son and south of the Gaṅgā was the janapada of Magadha. It was bounded by the Son on the west, the Gaṅgā on the north and the spurs of the Vindhyan plateau which touch the Gaṅgā near Monghyr on the east, and Vindhyan forests on the south. This janapada should normally be included in the eastern lands but since it lies on the borders of the 'Eastern' and 'Middle Countries' and also because the territory of Magadha annexed lands to the west of the Son, the Purāṇas thought it fit to include Magadha too in the 'Middle Country'.