Fangs, that would have been about 40 years ago. Up until the Parks Hwy was completed in the early 70s, the only way to get to McKinley NP, as it was known at that time, with your own vehicle was to drive the Denali Hwy, from Paxson to Cantwell and then the short distance north to the NP. Two or three bridges held up completion of the Parks Hwy for years. The bridge across the Tanana at Nenana, the bridge over Hurricane Gulch and I think the last bridge south to be finished was over the Big Su. Most visitors went to the NP on the Alaska Railroad, either south out of Fairbanks or north out of Seward or Anchorage.
The Denali was actually a better gravel road back before the Parks Hwy opened as the federal govt. helped pay for the road maintenance. Now all the Denali Hwy maintenance is state, as far as I know. Not a real high priority for the state on roads to keep up.. It just doesn't get much maintenance these days.
I drove in to McKinley Park on my first driving trip to Alaska in 1962. To get from Fairbanks to Anchorage then, you generally used the Richardson Hwy. So it was just a few hours drive from Paxson over to the Park. The 150 miles of good gravel road seemed great after having done over 1,000 miles of gravel on the Alaska Hwy. I have a lot of good memories of those early driving trips.