This is a hard one for me. Mostly cause I don't really have 'old friends'.
I have people I hung out with in school, though I was mostly the hanger on. I have people I know, who I still don't know well enough to ask them to go to a bar or movie or... anything else with me. (and no I'm not trying to get sympathy here, it's just the way it is)
The closest thing I have to an oldest friend, would be my aunt, my uncle, my sister and my little brother. They're the ones I know I can always rely on.(which probably explains why I value family relationships over either friendship or romantic ones.
Hell the closest thing I have to a real (non family) friend is well Andrea.
And I've never even met her.