Fire fighters warn that winter in the Macedon Ranges brings dangerous road conditions.
Gisborne CFA Lt Peter Harry says black ice is common in this area and it is a wake up call to drivers.
"It can be like driving on an ice skating rink with absolutely no control, and worst of all you don't know it's there until its too late".
Black ice is invisible and caused when wet road surfaces freeze after temperatures drop below 0c. The most common places it forms are on bridges and overpasses as the cool air flowing underneath lowers the road temperature.
Emergency services are asking drivers to be aware of the conditions and take extra care on cold mornings.
"The peak time is usually an hour os so either side of sunrise on cold mornings- if the conditions are right, all hell can break loose. We have had mornings in the past where dozens of cars have crashed in the space of an hour".