Denali is awesome but don't make it your only focal point. There will be so many gorgeous places before you even get to Denali. Canada and the Yukon in many places can be just as beautiful as Alaska.. sometimes more so. Once you enter Alaska you really need to do the full circle and check out each area. This is a trip of a lifetime. Many do it more than once but I'd say most do not. If you're retired and have time plan on using as much as you can. Plan to cross from the lower 48 into Canada by the end of May and spend all summer on the trip.