I spent part of summer 2016 in Silverthorne (exit 205) playing a show at the theatre company there. Even though you're driving downhill to that exit, the elevation is still around 10,000 feet (3050 meters). I live at around 1300 feet (400 meters) elevation so that air was pretty thin for me. I didn't get too much quality sleep for the 6 weeks (no metric conversion) I was there.