Icy roads have meant extra work for gritters in Conwy
Motorists taking to the roads for the Christmas getaway have struggled with icy conditions in many parts of Wales.
Gritters worked around the clock but fresh snow in the north of the country led to some road closures.
The Met Office had issued a severe weather warning due to concern about ice on roads.
Icy conditions were expected to continue into Christmas Day with temperatures dropping close to freezing or below overnight.
There was snow in Wrexham and Denbighshire overnight and the A542 was closed at the Horseshoe Pass before later reopening.
Driving conditions were also said to be hazardous on the A469 Caerphilly mountain road.
Meanwhile, a water main burst near Holywell in Flintshire.
Welsh Water said the burst in the early hours affected water supplies to several hundred customers in Lixwm, Holywell and the Cilcain and Pantymwyn areas of Mold.
The burst was in Bryn Cerrig, Lixwm, and most supplies were back to normal by mid morning.
Dwr Cymru at 1730 GMT said the main had been repaired but some householders might experience problems of temporary loss of supply or low pressure for a couple of hours until supplies returned to normal.
The company apologised and said it was unable to say what had caused the burst and if it was related to the weather.
The Met Office advised motorists to take extra care on the road and said drivers should refer to the Traffic Wales service for further advice on road conditions.
An elderly man was airlifted to Ysbyty Gwynedd in Bangor after his car was in a collision with a lorry at Cemaes Bay, Anglesey.
A woman pedestrian was taken to Wrexham Maelor hospital after she was involved in an accident with a car at Gwernymynydd near Mold.
Dyfed-Powys Police urged motorists to take extra care, saying sheet ice was making driving very difficult.
We've been exceptionally busy over the last week and seen a lot of patients suffering from fractures
Mike McCabe, A&E consultant
They reported numerous shunts and minor accidents throughout the force area.
Carmarthenshire council urged motorists not to travel over the next 24 hours unless absolutely necessary.
First Cymru suspended bus services between Resolven and Neath via Clyne due to ice on the road.
The National Botanic Garden of Wales in Carmarthenshire was closed due to ice causing "treacherous" conditions but due to reopen on Boxing Day.
An accident and emergency consultant in Swansea has also warned pedestrians to beware of hidden icy patches on pavements following a "spate" of falls.
'Hazardous icy patches'
Mike McCabe said: "We've been exceptionally busy over the last week and seen a lot of patients suffering from fractures, particularly wrists, ankles and shoulders, as a result of slipping on ice.
"Elderly people are particularly at risk, and if they don't need to go out, they should stay indoors."
BBC Wales weather forecaster Derek Brockway said icy conditions were expected to continue into Christmas Day.
There was also a chance of fog patches, which could be dense and freezing in places, overnight and into Christmas morning.
Mr Brockway added that Boxing Day was expected to be milder with a few showers, but it could turn colder again next week with a risk of more snow.
Boxing Day sporting events could also be affected by the weather.
Wrexham FC will inspect its pitch on the morning of the game against Altrincham.
The pitch is currently frozen but the club is hopeful that a predicted improvement in the weather will allow the game to go ahead.
Cardiff City FC has promised its Boxing Day home game against Plymouth will definitely go ahead following the "final commissioning" of the under-soil heating at the new Cardiff City Stadium.
Saturday's home match against Leicester City had been postponed due to an unplayable pitch.
In rugby, Scarlets' match against Ospreys on Boxing Day and Blues' game against Dragons on Sunday are both expected to be on.
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