In the Elder Days, the lands of Aman and Middle-earth came close together in the cold North of the world, separated only by a narrow strait. There the waters of the Outer Ocean mingled with those of the Great Sea, and where they came together they formed a churning field of ice: the Helcaraxë or Grinding Ice. On its western side was the bleak and misty land of Araman in the north of Aman, and on its eastern shores lay Middle-earth.

After the Darkening of Valinor, Morgoth and Ungoliant escaped through Araman and crossed the Grinding Ice to make their way into Middle-earth, the first to cross the Helcaraxë. Soon afterward, the Noldor came this way after exiling themselves from Valinor. Fëanor had taken their ships and crossed the Sea somewhat to the south, abandoning Fingolfin and his people on the western shores. Rather than return to the Valar, they instead marched into the far North and began the passage of the Grinding Ice, as the Moon rose for the first time. Many were lost in the dangerous crossing, but many more survived to reach the shores of Middle-earth.