Helcaraxë

Helcaraxë was the perilous icy wastes that formerly lay between Araman (a region in the north of Aman) and Middle-earth in the far north of Arda. Here met the Encircling Sea and the Belegaer, creating "vast fogs and mists of deathly cold, and the sea-streams were filled with clashing hills of ice and the grinding of ice deep-sunken."

After the beginning of the First Age, when the Elves awoke, Oromë decided not to lead the Eldar of the Great March there, on their way to Valinor, because of the ice and extreme cold, but rather took them by the Sea.

Escaping the pursuit of the Valar after destroying the Two Trees of Valinor, Morgoth and Ungoliant fled to Middle-earth across the treacherous wastes of the Helcaraxë. Later, Fingolfin and his people also made their way into Beleriand across the Helcaraxë. Many died while crossing it, including Elenwë, Turgon's wife.