Originally Posted by milepig

This part is actually fairly easy if you pay attention. When you leave concourse C you'll go down an escalator and then take a people mover through a tunnel (with lots of blinking neon tubing that earned it the nickname "death tunnel", but I digress...).

At the far end you'll see a very tempting long set of escalators going up. DO NOT TAKE THAT SET. Instead go around them, and you'll see a second set. These are the ones you want, and they lead one level up to baggage claim, from there take any escalators marked "UP" one more level to ticketing and then look for the escalators to the ATS shuttle train. They're opposite the ticketing desks, sort in the middle of the area. You'll walk through a little overpass and then down to the station. Terminal 1 is the end of the line, so all trains will go to the INTL terminal, just get on the first one.