I'm told by someone with a doctorate (not in religious studies) that Heaven and Hell are exactly what the bible says they are: opposite destinations in the afterlife.

However, they exist in a "different dimension," so to speak, so you can't fly or dig to them.

When you're in one, after death, you'll know instantly which.

Since God is loving and all-forgiving, it may be possible for certain non-Christians to go to Heaven, but my friend does not recommend testing the theory.

When I asked him how sure he was of these things, he replied, "Close to 100%. I can't say absolutely 100% only because this life is the only one I've actually experienced."