Rangers of the North
Isengard, or Angrenost (S.: Iron Fortress), was one of the three Fortresses of Gondor, and held within it one of the Realm’s Palantiri. In the latter half of the Third Age it came into the possession of Saruman and become his personal realm, Nan Curuníri.
Built in the Second Age around the tower of Orthanc by the Númenoreans-in-exile in the days of their power, Isengard’s location is at the north-western corner of the Southern Kingdom of Gondor, guarding the Fords of Isen from enemy incursions into Calenardhon, and with the fortress of Helms Deep to its south, protected the Gap of Rohan.
A natural, circular stone-wall surrounds the broad plain, and in its center the Tower of Orthanc. There is only one gate, facing south.
The river Angren (or Isen) began at Methedras behind Isengard, which also forms its northern wall. The other three sides are guarded by a large wall, known as the Ring of Isengard, which is only breached by the inflow of the river Angren in the north-east through a portcullis, and the gate of Isengard at the south, both shores of the river.
During the time of the Steward of Gondor Beren, Saruman the White reappeared from the East, offering to guard Isengard. Beren gladly gave him the keys to Orthanc, and Saruman settled there. After him the valley became known as Nan Curunír, or “Wizard’s Vale”.
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