The Doors of Morning (Q. "Arinandondi") also known as the Gates of the Sun (Q."Osto"), the Gates of Morn and the Gates of East, were the gates in the Utter East of the World where the sun came through after the night.It was said the Númenóreans had discovered them on their vast journeys so it does seem they had a physical equivalent on Ambar though they led to the Outer Darkness and thus pierced the Walls of Things.
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