The Ered Luin or Blue Mountains, also known as Ered Lindon , is the mountain range at the far west of Eriador , in J. R. R. Tolkien 's fictional world of Middle-earth .
During the First Age , the Ered Luin was an unbroken line separating Eriador from Beleriand . Seven rivers arose in it on the western side, and the land these rivers flowed through was known as Ossiriand , and later also as Lindon , therefore the mountains were sometimes referred to as the Ered Lindon. The dwarven cities of Belegost and Nogrod were located in this range.
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