Yep, it was early June 1973 (I think?) and the Highway Dept. crews apparently hadn't gotten to the Denali yet (maybe too busy with the Parks). It was raining and there were some hills that a heavily loaded, RWD car just didn't want to climb and some deep ruts that we didn't avoid. When the rain stopped and the area near the Susitna dried out, there were clouds of dust to go along with the clouds of mosquitoes. Of course, most of the dust was created by the our project helicopter flying in and out of the fishing camp we were staying in (somewhere just west of the river and south of the highway?). Our pilot was landing by "feel" because the entire chopper was completely enveloped in dust. Not one of my fondest trips to Alaska!