The Andrath was a defile between the Barrow-downs (to the west) and the South Downs (to the east) in Eriador. Through this narrow way just south of Bree passed the North-South Road (Greenway).
When the Black Riders came up the Greenway in search of the One Ring, the Black Captain established a camp at Andrath. From there he sent some Riders out to patrol while he visited the Barrow-downs.