In the originally, Earth Prime was the real universe that you and I come from. In Flash #179, while hunting a monster called the Nok, he got stuck in Earth Prime. He met his editor, Julius Schwartz, and the duo somehow created a new cosmic treadmill to get Flash home. It was stated that the writers of Earth Prime based their comics on actual people and events (just in alternate universes). In Flash # 228, Earth Prime's Cary Bates discovered he could effect the events in Earth One and went on a rampage there, only to be stopped by Elliot S. Maggin. Earth Prime began to differ from our reality and it had two heroes: Ultraa and Superboy-Prime. Earth Prime was destroyed in Crisis of Infinite Earths # 10. In Infinite Crisis # 6, Superboy-Prime conviced Alexander Luthor to draw inspiration for his new "Earth" from Earth Prime (he calls it an "ideal world"). He went looking for it and (in a nod to the original Earth Prime) looked at readers and reached out for our reality. In 52, Earth Prime was restored.