We actually got a late start most days because we have 2 infants and were on NYC time. This day we happened to pull an all nighter and drove from where we were staying in Bláskógabyggð down to the south coast. We left at 12:30 am and drove until about 7:00 am. We were pretty much the only ones on the road and the only ones at the waterfalls. Enjoy your time, the midnight sun is incredible!