It started off as an unconventional way to chart an itinerary for a months-long, post-retirement cycling trip, with Vincent Berthelot offering to personally deliver letters across France and see where the whims of the writers would take him.
What swiftly became clear was the transformative power of hand-delivered letters, at times reuniting family members and long-lost friends. Eight years on, his idea has swelled into a movement, with more than 100 people now crossing continents to make offline connections in a virtual world.