A scheme to protect Cornwall's ancient artefacts from thieves by micro-chipping them has begun.
The process does not damage the crosses
The project, which uses electronic tags to make items like granite crosses less attractive to criminals, is already being used on Dartmoor in Devon.
Created in medieval times, the crosses marked boundaries and showed the way to the parish church.
In the past 20 years there have been a number of thefts of the crosses to feed a growing market for granite artefacts.
One hundred of Cornwall's most vulnerable wayside crosses have been identified and will be fitted with microchips.
Funding for the process, which causes no damage to the cross, is being carried out with the help of grants from a range of organisations, including the Heritage Lottery Fund and English Heritage.
Ann Preston-Jones, senior archaeologist with Cornwall County Council, said: "It is sad that protection of this sort should be needed, as the crosses are monuments of great importance to Cornish identity and often well-loved and cherished by local communities.
"Hopefully this modern technology will help to prevent any further attempts to steal these ancient monuments."