Hogwart's Express Space

[ats_fhc3]

No: HPFGUIDX 43874

Okay, I'm positive that magical space vs. real space was debated 
before, BUT as I was driving about aimlessly at work last night, I 
was wondering if anybody had anything to offer to my question.

Okay, if Harry and Co. need to go through the wall to get to 
Platform 9 3/4, wouldn't that mean that Hogwart's Express has its 
own magical space? And, if it does, how is it, then, that Harry and 
Ron were able to take a car (enchanted, but a Muggle car, 
nonetheless) parked in a non-magical parking lot, make it invisible 
and fly it upward, spot Hogwart's Express pulling out of the train 
station, and follow it from London? Is there some dimension or 
invisible line that they crossed, to get to magical space?

You are now welcome to tie your brains in knots, because I am 
without canon until October.
-Acire, who wonders if anybody else has trouble associating 'Snape' 
with 'wizard', and who also must mention Snape in every post.