There are loads of references to Heaven in the Bible to consolidate, but generally Heaven is the destination place of the faithful. It is not physical but spiritual, being in the very presence of God. God is a spiritual being that is impossible for human eyes to see and Heaven, also is outside the boundaries and understanding of man as he lives in the physical universe. The only base analogy we can come up with is some floaty clouds with angels playing harps somewhere in the sky as �Heaven� referred to Heavenly or Celestial bodies (the dwelling place of God and His angels).
Originally Heaven was meant to be in the Garden of Eden, but when Man sinned against God, man was cast out of the garden. I suppose it�s a bit like the Egyptian Fields of Hotep, the Greeks Elysian Fields, or the House of Hades, Dis Pater or the old Norse, Valhalla (House of the Slain). Most ancient mythology believed that the afterlife was a continuation of the life on earth and after death you were �judged� and either sent to join and sit with the gods (Heaven) or to wander alone in the underworld (Hell). The Egyptians were a bit more optimistic and left maps to Sekhet Hotep in their Pharaohs tombs, so the dead could find their way once their heart was weighed and they were judged.