(disclaimer, I'm a native Spanish speaker, so I find it funny that both 'ser' and 'estar' use a single word in some languages)
The point isn't that you sometimes use 'ser' and sometimes use 'estar'. They're two different concepts.
In short, "ser" relates to the very being of something, while "estar" is (usually) a temporary condition. That's why you say "Estoy enfermo" (I'm sick) and "Soy zurdo" (I'm left-handed); one is (hopefully) temporary, while the other is not only permanent, but part of my self-definition.
Usually, for location you use "estar" because at one moment you're at one place but later you can be somewhere else. The place you are is a temporary condition.
Events, on the other hand, usually have their whole existence tied to a single place, so they "are" there until they're no more. But, if it's a mobile event (like a parade, or a voyage), then you can say:
El desfile aún no llega, está muy lejos.
El crucero está aquí, llegó ayer.
But, if your location specification is wide enough to encompass the whole event, you again use "ser":
El desfile será desde este lugar hasta este otro.
Fue un crucero a través del atlántico.
Of course, in these cases it's more common to refer to the moving entities and not the moving event.