Survival Zone
From superman.nu: Supermanica
Survival Zone
A Phantom Zone-like dimension discovered by Zor-El, Supergirl's father and Jor-El's brother.
As Argo City was being destroyed, Zor-El and his wife Alura save themselves by projecting themselves into the Survival Zone. Previously, they were believed to have perished in the disaster by both Supergirl and Superman.
Years later, they are able to make telepathic contact with their daughter, Kara Zor-El (Supergirl), who eventually frees them from the strange dimension (Act No. 309/2, Feb 1964, "The Untold Story of Argo City").