Counter-Earth is a parallel world to Earth were the animal human hybrids rule, but human are treated badly.
After the High Evolutionary fled Earth he established himself on Counter-Earth and took over. John Jameson flew a shuttle there but Venom and Carnage ruined the mission. Spider-Man followed on a second shuttle where he joined a human resistance group against the High Evolutionary. Meanwhile, Venom and Carnage tried to take over the planet.
Currently the only version of the world outside the comics.
In the Comics
It was created by the High Evolutionary, while the series states he found it.
There are versions of Reed Richards, Victor Von Doom, and Bruce Banner who are scientists but never gained powers. Though Reed eventually became twisted and used the name Brute. Tony Stark was never injured. Peter Parker died from radioactive over-exposure. There is also a Doctor Strange named Necromancer.
Adam Warlock became champion of the planet.
Under orders from the Beyonder, it was moved to a museum out of the solar system.
It was destroyed by Thanos.