Well, here's an amazing depiction from a Sumerian tablet dated 5th millennium BC:

Now some say that this depicts our solar system, including the recently discovered dwarf-planets such as Sedna, what is now an asteroid belt and the controversial Nibiru (see the planet between the couple and the priest) for a total of 12. Others say this theory is completely unsupported.

Although, indeed, Sitchin and his followers have yet to prove that it is the solar system depicted there, I still haven't come across any overwhelming arguments that it is not. In fact it looks pretty damn incredibly close to our solar system.

Something to be further investigated...