have become essential wear again amid the return of winter conditions, something that has led to a mountain rescue being carried out on Britain's second highest peak.
Members of Braemar Mountain Rescue Team were called out after a party of nine, which included six teenagers, became caught in the cold and snow on the mountain, where high winds were creating a chill factor of -35C.
Royal Navy rescue helicopter from HMS Gannet airlifted the group to safety from the 4,295 ft peak.
With the cold weather back after the exceptionally mild March, those who go walking
will be wise to take with them Ordnance Survey maps
and a compass, extra warm clothing and waterproofs
Ben Macdui is one of five mountains in the Cairngorms over 4,000 ft, the others being Braeriach (4,252 ft), Cairn Toul (4,237 ft), Sgorr an Lochan Uaine (4,127 ft) and Cairn Gorm itself (4,084 ft).