Gilgamesh does not exist

Gilgamesh was king of Uruk right? Then how do you know that Uruk existed? Written in the books or gasp wikipedia? I say without proof that Uruk existed, Uruk does not exist. Therefore, Gilgamesh does not exist.

But have you been there? How can you even tell that it's indeed the fabled Uruk that "existed" 2000 years ago? You accept every little bit of shit that's fed to you don't you?