I think heaven is mostly a state of mind...a level of consciousness. When one is filled with peace, love, and joy one is in heaven, regardless of where one is. We all have had moments like that back in childhood, and probably a few since. I remember falling asleep in the back of my parents' car on long trips at night. That was a lovely feeling. I remember moments of heaven with lovers and friends or just out in nature when everything seemed absolutely perfect. It was my own complete acceptance of reality at those moments that made the experience heavenly. One could theoretically feel that way all the time, if one totally accepted the present moment. That, in fact, is what is involved in the quest for enlightenment...exactly that state of mind where one is totally accepting of reality in every moment, regardless of outer conditions. It's possible to achieve that, but very few people ever do. I've been around one or two who have achieved it, and the benefits that it has added to their lives and their personalities go beyond measure. Because of observing that I know it's possible.

Quite aside from that, there are reputedly numerous heavenly regions or dimensions in what could be called the Astral Worlds...which are not physical worlds but mental dimensions. You can go there in dreams, you can also go there as a spirit (after physical death). They are indeed, as Jerry says, beyond the conception of the Earthly mind...if the stuff I've read about them is true. ;-) Whether it is true or not, however, no one here can prove one way or another.

There are also reputedly many hellish regions in the Astral Worlds, as well as more mundane regions...as there is a "place" for absolutely every form of mental/emotional consciousness there. If you are bored...there's a boring place. If you're scared...there's a frightening place. If you're depressed...there's a depressing place. If you're amused...there's an amusing place. And so on...ad infinitum.

Anything the mind can come up with, it can have. God is generous that way. My advice is: come up with something loving, peaceful, joyful, and inspired! It "beats hell" out of being scared, bitter, or depressed. Quite literally, in fact. You get exactly what you have decided to get in your own mind...what you think you deserve, and specially what you choose to project onto other people. It bounces right back at you.

That's why it suggests in Christ's teachings not to judge others.