Dominic Nelder spent his summer holiday travelling the London Underground in an attempt to make it a friendlier place after the terrorist attacks in July.
In August the 34-year-old history supply teacher donned a traditional City gent's suit and bowler hat to greet around 20,000 people.
He was inspired to do his nine-hour-a-day non-stop commute after reading about a woman who had become so scared of travelling that she wept on her first journey after the bombings.
"Every other holiday I've been thinking about lesson plans, ideas, getting resources. This holiday I've had some lovely moments," said Mr Nelder, who reckoned that the Central Line commuters were the friendliest.
"People have come up and said 'You have really put me at ease'."