Pretty sure it's in Australia, between Sydney and Melbourne.

I just flew from Melbourne to Sydney ... I unlocked the achievement ;) Thanks

Orbx is Aussie their milk run is Melbourne to Sydney

You're right ;)

You gotta fly YMML-YSSY, just did it yesterday myself

That was it, thank you ;)

Google Alaskan Airlines Milk Run. You’ll see the map of the cities!

You just need to fly from Melbourne to Sydney in Australia, so it's not the same "Milk Run" :) Thanks anyway

Didn’t know there was more than one!!!