Jogging

One day I decide to go jogging...so at the crack of noon I lace up my
Keds and head out for a jog. I run along a flat road for a while, then
I come to a hill, and run up the hill. Once at the top, I immediately
realize the folly of my efforts, and immediately head back down the
hill, following the exact same path back to my house where I realize I
have been gone exactly 2 hours.

Now, here's the question. Running on flat ground I can make
8mph...going uphill I am traveling at 6mph, and going downhill I am
covering 12mph.

The question is...How far have I jogged in those 2 hours?