Rohan is bordered to the north by the Fangorn forest, home to the Ents (tree-giants) led by Treebeard, and by the great river Anduin, called Langflood by the Rohirrim. To the northeast are the walls of Emyn Muil. After the War of the Ring, the kingdom is extended northwards over the Limlight to the borders of Lothlórien. To the east are the mouths of the River Entwash, and the Mering Stream, which separated Rohan from the Gondorian province of Anórien, known to the Rohirrim as Sunlending. To the south lie the White Mountains (Ered Nimrais). To the west are the rivers Adorn and Isen, where Rohan borders the land of the Dunlendings. To the northwest, just under the southern end of the Misty Mountains, lies the walled circle of Isengard around the ancient tower of Orthanc; at the time of the War of the Ring, it had been taken over by the evil wizard Saruman. The area of the western border where the Misty Mountains and the White Mountains drew near to each other is known as the Gap of Rohan.