The Land of the Sun or "Sun-Lands" is an empty land east of Middle-earth where the sun rises at dawn. Nothing is known of its geography except that there was a curve-shaped mountain range called the Wall of the Sun that corresponds to the Pelóri Mountains of Aman.
In the Ambarkanta it is called the Dark land of the Sun. There is a possibility the Númenóreans visited it.
In the game Middle Earth Role Play by Iron Crown Enterprises, a Sindarin name for the land — Romenor (Easternesse) — was given, although it does not appear in any of Tolkien's writings.