in Denali n.p.,access to the public park only goes about 50 miles. If you take the private shuttle, it goes about 125 miles into the park. It's more expensive, but you get to SEE 10 TIMES MORE WILDLIFE, plus a set-down lunch, panning for gold, and dog sled demonstration. We went in 2007, and had a friend tell us about the private, reservation needed 6 months in advance, 6 course lunch at the private home.
It cost about $125/head, but if you want to see wildlife 10 feet from the bus, this is the trip i would recommend. we are going again in 2015, and have reservation for this. Its the only reservation we may make.
The trip takes 12 hours and stops at all the other stops along the way. Carry snacks and drinks with you.
have a safe trip and keep it between the markers.