The Duchess of Cornwall has met inmates and the volunteers who help keep them connected to their families during a visit to a prison in Wiltshire.

Camilla chatted with prisoners at HMP Erlestoke near Devizes and met helpers who have stepped in to ferry relatives from the local train station to the facility on visiting days.

A transport club was set up last year by the charity Friends of Erlestoke Prison, but the Duchess heard there was still a desperate need for more drivers to take people to and from the station to see their loved ones in the Category C men’s prison.

The Duchess told volunteers Carol Part, 72, and Heather Mullins, 60, who help out by with the driving: “I always say this country would collapse without volunteers. You are the backbone of this country.”

She added: “I imagine it must make a big difference to their lives because otherwise how would they get there?”

Camilla is patron of the charity, which also helps support offenders with the challenges of resettlement and rehabilitation.

During her one and a half hour tour, the Duchess also met prisoners and mentors taking part in literacy schemes and offenders learning vocational skills such as bricklaying and plastering.

Camilla previously visited HMP Erlestoke in March 2012, when she watched prisoners and professionals perform a version of the hit musical Les Miserables.

The prison provides a secure environment for up to nearly 500 inmates. Sentences range from very short sentences to life sentences.