Fords of Isen
|The Isen came down swiftly from its sources above Isengard, but in the flat land of the Gap it became slow until it turned west; then it flowed on through country falling by long slopes down into the low-lying coast-lands of the furthest Gondo and the Enedwaith. Just above this westward bend was the Fords of Isen. There the river was broad and shallow, passing in two arms about a large eyot, over a stony shelf covered with stones and pebbles. Only here, south of Isengard, was it possible for large forces, especially those heavily armed or mounted, to cross the river.|
|Unfinished Tales, The Battles of the Fords of Isen|
The Fords of Isen was located almost in the middle of the Gap of Rohan, some 15 miles northwest of the mouth of the Deeping-coomb, and some 30 miles south of Isengard. From the Fords of Isen to Edoras, the distance was some 135 miles by the road.
Isen = Sindar: (SÓr) Angren.
Fords of Isen = Sindar: Ethraid Engrin (plural), also AthradAngren (singular).