William and Kate release an unseen family photo from Snowdon to thank mountain rescue volunteers on awareness day

The picture was taken in June at the foot of Yr Wyddfa, with the family surrounded by the Llanberis Mountain Rescue Team, the busiest rescue unit in the UK. It marked the end of Catherine's Three Peaks Challenge, when she climbed Ben Nevis, Scafell Pike and Snowdon inside 24 hours. She raised money for the Royal Marsden Cancer Charity. Prince William is Royal Patron of Mountain Rescue England and Wales.

The caption, signed 'W & C', praised volunteers for their 'courage and service'.