The Hitchhiker's Guide to the Galaxy is a wholly remarkable book... The introduction begins like this:

"Space," it says, "is big. Really big. You just won't belive how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanutes to space. Listen..." and so on.
...
To be fair, though, when confronted by the sheer enormity of the distances between the stars, better minds than the one responsible for the Guide's introduction have faltered. Some invite you to consider for a moment a peanut in Reading and a small walnut in Johannesburg, and other such dizzying concepts.

The simple truth is that interstellar distances will not fit into the human imagination.

--Douglas Adams, Hitchhikers' Guide to the Galaxy, Ch. 8.