There are two answers to this. One is Uranus, or Ouranos, who IS the sky and heavens, father of the Titans, grandfather of Zeus, Poseidon, Hades, Hera, Demeter, and Hestia. It could also be Mount Olympus, where the gods lived.
Hera
The Elysium Fields
Hades is not only Hell. It's the realm of the dead, and there are a few different areas, including the Fields of Punishment and Tartarus, which were Hell, and Elyssium and the Isles of the Blest, which were something like Heaven.
Because, if they were females, they'd be GODDESSES!
The main god of Greek mythology would be Zeus, the king of the gods. for he is ruler of heaven and earth. he is also king of the world.
Hades, which is in Greek and Roman mythology, is both a place for heaven and hell. So all dead people go to Hades according to Greek and Roman mythology.
In Greek mythology Crius was one of the Titans. The Titans were offspring of Uranus (Heaven) and Gaea (Earth)
Prometheus.
Prometheus
In Greek mythology, the giant who supports heaven on his shoulders is Atlas. He was a Titan condemned by Zeus to carry the heavens for eternity.
No one on Earth has been to Heaven, that I know of. So technically this question can only be answered by opinion. On my opinion, no, Mount Olympus and the greek gods are not real and in Heaven. Mount Olympus does however exist in Greece. But on the other hand, the greek gods are myths, therefore, they do not exist.
The off-spring of Gaia and Uranus - mother earth and father heaven- were Oceanus, Coeus, Crius, Hyperion and Themis. Let it also be stated that Uranus was also her soon as well as husband