A second roading manager questioned the sense in using it when snow was forecast, and sleet was already falling at lower altitudes.
The "road'' - 17km of mud and clay within the Southland District and 12km of rock within the Central Otago District (CODC) - has a long history of weather-related misfortune.
In a snowstorm in 1863, 30 gold miners perished in the area as they tried to walk to safety.
In more recent times, there was a fatality during a 4WD trip in 2008 and there have been numerous occasions when those using the road have been caught out by the weather.
The road provides access to the Department of Conservation's Kopuwai Conservation Area and is used by high country farmers, but much of the traffic is generated by 4WD enthusiasts.
CODC executive manager of infrastructure Julie Muir said yesterday there was sleet at Coal Creek, near Roxburgh, on Sunday morning.
"So I am surprised anyone would have gone up there, given what the weather was like.
"There are signs on the road saying it is a dry weather road and weather conditions can change.''
Ms Muir, who has been dealing with the road for 18 years, said her council no longer closed the road for the winter because it effectively closed itself.
"On our side ... it gets a snow cap and ice cap and you actually physically cannot get up the road.
"Because of the ice pack that goes across it, it actually naturally closes.''
The Southland District Council at the southern end takes a different approach and officially closes the road at Queen's Birthday Weekend, the first weekend in June.
The closure process takes at least two weeks, making it impractical to close the road at short notice.
Roading engineer Bruce Miller said Queen's Birthday was chosen because it was the usual time for a good fall of snow.
He suspected the group caught out might have been making a last trip before the gate at the southern end was locked for the winter.
Mr Miller said aside from the road being used for farming, ''it's only a playground''.
Questions had been asked previously about whether it should be closed permanently, he said.
"That would be the answer I suppose, but I don't know how that would go down with the public.''
