I only know the basics: He started in Colorado, and went to Los Angeles, Monterey, then a "tour" from there to Washington (state), and on to Anchorage. Just putting Denver, CO>Los Angeles, CA>Monterey, CA>Anchorage, AK into Google Maps yields a distance of 4,510 miles, so I expect his trip will easily cover over 5,000 miles.
For a Kiwi-friendly comparison, it is right about 5,500 miles as the proverbial crow flies from Auckland to Tokyo.