4. The Savage Land
The Savage Land is a prehistoric land in Marvel Comics Universe. It is a warm, tropical preserve hidden within Antarctica. The Savage Land was was created during the Triassic period by the alien Nuwali for another alien race, the Beyonders, for observation and research purposes. They used climate-controlling technology to keep it tropical amidst the otherwise freezing temperatures. After they got bored with their observation and research, they left, but they left behind a thriving ecosystem that would continue to exist until modern times. At one point in its history, a group of humans from Atlantis discovered the Savage Land and claimed it as their home. They experimented on the various species living in the Savage Land and forced them to work for them until they revolted. The Atlantians used the climate-controlling technology to expand the Savage Land. However, they were overthrown by the natives and the expanded areas in the Savage Land remained after they left. Many years later, the Savage Land was discovered by a man named Lord Robert Plunder who took back a metal which could liquefy all other metals. The discovery of this metal meant that others would want to steal his discovery, so he took his eldest son Kevin, and went back to the Savage Land to live in forced exile. However, Lord Robert Plunder was killed by a local tribe of Man-Apes, and Kevin grew up in the Savage Land, becoming the hero known as Ka-Zar. The land itself and the various creatures who reside there would make for one hell of a movie setting and, in the comic books, the characters have interacted with the likes of the X-Men, Thanos and the Avengers, so it's not as if it would have to be an exclusive, standalone movie. Indeed, in Iron Man 2, Tony Stark opened a case that belonged to his father, Howard, which contained the first Captain America comic book, a home video, a journal and blueprints for the original arc reactor. If you look closely at the scene, you'll also notice a satellite photo and a map of Antarctica. On said map you can see an area annotated that matches up with the Savage Land's location in Marvel Comics continuity - so it may already exist in the Marvel cinematic universe, along with the likes of Wakanda and Atlantis which were also indicated on the map.