The importance of having Ordnance Survey maps when out walking may have been emphasised by the case of three hikers rescued when their emergency call was detected by the coastguard 70 miles away.

Watch manager at Humber Coastguard Mike Green said the sea rescue body was "very fortunate" to pick up the 999 call, made by the walkers after they got lost on the moor between Arncliffe and Buckden.

The coastguard then liaised with North Yorkshire Police and the Upper Wharfedale Mountain Rescue Team to help find the lost group and bring them safely down.

Walkers heading for the hills who have Ordnance Survey maps to help them navigate may be much less likely to get lost and need help to get down, while a walking GPS could help pinpoint their exact position.

One place where a walking GPS may temporarily be less useful is along the Norfolk Coastal Path/Peddars Way as it passes the Stanford military training base near Thetford, Grough revealed last month.

This is because signal jamming will be in operation at times between September 19th and 23rd and possibly again next month, which may suggest a map should be taken as well.