Walking for charity has become a habit for Christopher Schrader over the past four years.
Last month he completed a 51-day, 1,600km trek across the Mongolian Gobi Desert,.
The world's fifth largest desert - Asia's largest - poses a gruelling challenge with its rapid fluctuation of temperatures over a single day, ranging from 5degrees Celsius to 45 degrees.
Christopher, who is originally from the Netherlands, and moved to Hong Kong with his family when he was a baby, joined 13 other international adventurers on the Gobi Crossing Expedition.
Led by British desert explorer Ripley Davenport, the trekkers battled severe dust storms, blizzards and heatstroke to raise funds to educate Mongolian children.
Christopher has been organising charity events since he was 15. He founded Youth Endurance Network, a group that runs activities such as last December's '24 Hour Race to Stop the Traffik', which involved about 180 Hong Kong secondary students running in a relay to raise awareness of human trafficking.