Mirkwood was the largest forest in Middle-earth in the Third Age. From north to south the forest covered approximately 425 miles. From east to west it was about 200 miles across at its widest point. On the southeastern side of the forest was the East Bight, a great clearing that cut into the woods. At this point the distance across Mirkwood was the shortest - about 75 miles - and it was known as the Narrows of the Forest.
Many of the trees of Mirkwood were ancient and very tall. The canopy of the forest was a thick tangle of branches that let in little light. Among the different kinds of trees were beeches and oaks. Fir trees grew on the slopes of the Mountains of Mirkwood in the northern part of the forest. There were also many dark fir trees in southern Mirkwood around the bare, stony hill called Amon Lanc.
The Forest River flowed through the northern part of Mirkwood from the Grey Mountains in the north to Long Lake east of the forest. The Enchanted Stream sprang from a source in the Mountains of Mirkwood and flowed north to join the Forest River. Another stream, whose name is not known, flowed east from the mountains into the River Running. The River Running passed through the easternmost edge of Mirkwood for a short distance.
The Old Forest Road was the main thoroughfare across Mirkwood from west to east. The road came down from the High Pass in the Misty Mountains and crossed the Anduin at the Old Ford before entering the forest. There was also an Elf-path farther north that could be entered through the Forest Gate on the western edge of Mirkwood.
Many animals lived in Mirkwood, including black squirrels and deer, some dark and some white. There were large black bats and dark-grey and black moths that were as big as a person's hand. Above the forest, black emperor butterflies lived in the treetops. Ordinary spiders also lived in the treetops, while down below dwelled the huge and terrifying Great Spiders who wove webs in the tree-branches and fed on warm blood.
In ancient times when the Elves began their Great Journey westward to the Undying Lands, some of the Elves were reluctant to cross the Misty Mountains and decided to settle in the woods along the Anduin. These Elves were of the kindred called the Teleri, and those that remained in the woods came to be called Silvan Elves, or Wood-Elves.
The woodland Elves lived in small scattered communities at first. In the early part of the Second Age, the Woodland Realm was established in Greenwood the Great by a lord of the Sindarin Elves who had migrated eastward from Lindon. By some accounts, it was Thranduil who founded the Woodland Realm; by other accounts it was his father Oropher.
According to the latter accounts, Oropher and his people originally lived around the hill called Amon Lanc near the southwestern edge of Greenwood. But as Sauron grew in power in Mordor south of the forest, Oropher began to move his people northward. He may also have been trying to distance his realm from the realms of Lothlorien and Khazad-dum across the Anduin. The Wood-Elves settled in the fir-covered mountains north of the Old Forest Road. Their numbers increased and they roamed far and wide throughout the forest.
During the War of the Last Alliance at the end of the Second Age, Oropher and his son Thranduil led a great army to fight Sauron. Many Elves of Greenwood died in the war, for though they were courageous they were poorly equipped for battle and their forces remained independent of Gil-galad's supreme command. Oropher himself was slain during the assault on the gates of Mordor.
After Sauron's downfall, Thranduil returned to Greenwood with only a third of his army. For the first millennium of the Third Age, the Wood-Elves were at peace and their numbers grew again. During this time, the Northmen who lived east of Greenwood also increased and some made settlements in the eaves of the forest. The Men felled many trees to build their homes, creating the great clearing called the East Bight.
Around the year 1050 of the Third Age, Sauron came secretly to Greenwood and built a stronghold on Amon Lanc which became known as Dol Guldur, the Hill of Black Magic. A shadow fell on the forest at that time and it came to be called Mirkwood. It became dark and gloomy under the trees even in daytime, and the air was heavy and still. Evil creatures came to live in the woods, including the Great Spiders which were the spawn of Shelob, child of Ungoliant.
Thranduil and his people abandoned the Mountains of Mirkwood, which became infested with evil creatures. They moved northeast and built halls in a network of caves in the hills on the banks of the Forest River. A stream ran from the caves to join the Forest River and the Elves used it to transport goods to and from Long Lake and beyond.
The Northmen who lived east of Mirkwood were decimated by the Great Plague of 1636 and by the invasions of the Wainriders from the far East. Some of them moved to the town of Dale at the foot of the Lonely Mountain where the Dwarves had a prosperous kingdom not far from the Elvenking's Halls. In the latter part of the Third Age, some bold Men known as the Woodmen established settlements in the western eaves of the forest south of the Old Forest Road. Radagast the Wizard lived near the southwestern edge of the forest in Rhosgobel
In the autumn of 2941, Bilbo Baggins came to Mirkwood with Thorin Oakenshield and twelve other Dwarves en route to reclaim the Lonely Mountain from Smaug the Dragon. They entered the Forest Gate and took the Elf-path eastward, travelling for many days through the gloomy forest. At night they saw the eyes of many strange creatures watching them.
When they came to the Enchanted Stream, they saw a boat on the far shore and were able to pull it across the stream using a rope and a hook. As they crossed, Bombur - the fattest Dwarf - fell into the stream. The enchanted waters caused Bombur to fall into a deep sleep for many days, and the others were forced to carry him.
Bilbo climbed to the top of an oak tree to see if he could determine how much farther they had to go. It seemed to Bilbo that the trees stretched endlessly in every direction, for he did not realize that his tree was at the bottom of a valley which prevented him from seeing the edge of the forest.
Bilbo and the Dwarves were drawn away from the Elf-path by the lights of the Wood-Elves, who were feasting in the forest, but each time they approached the lights went out and the Elves vanished. On the third occasion, Thorin was captured and was imprisoned when he refused to tell Thranduil why he was in Mirkwood.
Meanwhile, the other Dwarves became lost and were captured by Great Spiders, who wrapped them in webs and strung them in the trees. Bilbo killed many of the Great Spiders with his sword Sting and rescued the Dwarves, but the next day they were imprisoned by the Wood-Elves. Bilbo once again came to their rescue and the Dwarves escaped down the Forest River packed in empty barrels that had been used to transport wine and other goods.
Several weeks later, Thranduil heard of the death of Smaug and he led a group of Elves to the Lonely Mountain. They found that Lake-town had been destroyed and they provided the Lake-Men with food and shelter. Thranduil and Bard of Lake-town tried to negotiate with Thorin, who refused to listen. But then an army of Orcs and Wargs arrived and the Elves of Mirkwood fought side-by-side with the Dwarves and the Lake-Men in the Battle of the Five Armies.
Also in the autumn of 2941, Gandalf convinced the White Council to attack Saruon's stronghold at Dol Guldur in southwestern Mirkwood. Sauron was driven out of Mirkwood, but he was prepared and he went in secret to Mordor. In 2951, he sent Khamul the Easterling along with one or two other Nazgul to reoccupy Dol Guldur.
Gollum passed through Mirkwood during his search for Bilbo and the One Ring. He ate what animals he could catch, and it was said by the Woodmen that he sometimes stole infants from their cradles. Eventually he turned south and went to Mordor.
Many years later, Aragorn caught Gollum and brought him to Mirkwood on March 21, 3018. Gandalf came and questioned Gollum and Thranduil agreed to keep the creature imprisoned. But Sauron's servants in Dol Guldur became aware that Gollum was being held prisoner in the northern part of the forest. On June 20, Gollum was at the top of a tall tree that stood alone in a clearing which the Elves allowed him to climb. He refused to come down and suddenly the Elves were attacked by Orcs and Gollum escaped.
Thranduil sent his son Legolas to Rivendell to report Gollum's escape. Legolas became a member of the Fellowship of the Ring who accompanied Frodo Baggins on his quest. Legolas fought throughout the War of the Ring at the side of Aragorn, the heir to the throne of Gondor and Arnor.
The War also came to Mirkwood. In March of 3019, Sauron's forces caused great ruin and set the woods on fire, but Thranduil and his people defeated them. On March 25, the Ring was destroyed and Sauron was vanquished. On March 28, the Elves of Lothlorien came across the Anduin and took Dol Guldur, and Galadriel threw down its walls. The shadow was lifted from Mirkwood and the forest was cleansed of evil.
Thranduil met Celeborn of Lothlorien in the middle of the woods on April 6, the Elves' New Year. They renamed the forest the Wood of Greenleaves and they divided it between them. The Woodland Realm of Thranduil was the forest north of the fir-covered mountains. The southern part of the forest below the Narrows became East Lorien and was part of Celeborn's realm. The land between the two Elf realms was given to the Beornings and the Woodmen. The Elves and Men of the Wood of Greenleaves remained untroubled for many years.
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