The source of the Altm?l is located close to the city of Ansbach. From here the river runs southeastwards as a narrow brook to enter the Altm?lsee (a lake) north of Gunzenhausen. After leaving Gunzenhausen the river describes a broad curve through the Frankish Alb. It enters the Altm?l Valley Nature Park, which is famous for its natural beauty: The meanders of the Altm?l River have cut deep gorges into the mountains of the Frankish Alb.
The Altm?l passes the cities of Treuchtlingen, Eichst?t and Beilngries. Behind Beilngries the river bed was straightened and integrated into a canal connecting Main and Danube. In spite of protests by conservationists this canal was opened in 1992 and destroyed much of the beauty of the eastern Altm?l Valley.
The Altm?l finally meets the Danube in Kelheim.