Rocky sure takes a curious route around the city of Philadelphia when he goes on those legendary runs around town, doesn't he? What kinda jamook goes from South Philly to Kensington to North Philly back to South Philly to the parkway... man my fingers are tired.
So just how far does Rocky run in Rocky II's training montage? Well, I'd bet with all that filming, Sly Stallone probably ran over a mile or two, which, to be honest, would probably get most of you/us winded. But Dan McQuade did the yeoman's work of mapping out all of the spots Rocky is filmed running through and tracked the mileage it would actually take to hit them all in order.
The run would be well over marathon distance.
Go check it out. Pretty damn entertaining stuff.