Fangorn Forest, called Entwood by the Rohirrim, is the last place where Ents live. It is named after the oldest Ent, Fangorn (Treebeard).
Fangorn forest is a forest beneath the southeastern flank of the Misty Mountains. It is the oldest part of treebeard's realm and the Ents retreated here.
Meriadoc Brandybuck and Peregrin Took go through Fangorn Forest and meet Fangorn (Treebeard). They persuade him of the danger that Saruman poses to the Ents and their forest. The Ents were angry at Saruman for instructing his orcs to cut down the tree to the south and west of the forest. Following the Entmoot, the rest of the Ents finally agree to march against Isengard taking Merry and Pippin with them; they also send Huorns to Helm's Deep to deal with the orcs there.
Aragorn, Gimli and Legolas also enter the forest whilst trying to and find Merry and Pippin. It is in Fangorn Forest that they encounter a white wizard. At first they believe it to be Saruman before realising that it was Gandalf, who they thought had been killed at Khazad-dum.
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