2.5 laps = 1 mile.
I agree that first thing in the morning is a great time to go out and run on these ships. There are usually a handful of runners/joggers and walkers, so you might occasionally need to slow down to get around a walker (depending on where you are on the track....it is wider along port/starboard than forward/aft), but if that's the worst of the problems -- and it is -- then it's hard to complain. My only complaint would be the one or two people who obviously don't notice that EVERYBODY else is going a different direction -- ha! There are signs to help with that (counterclockwise, as I recall).