Born in Tanchon, North Korea in 1924, Hwang San-Ung defected to South Korea in 1946 with the dream of becoming a competitive cyclist. Once in South Korea, Hwang competed in the cycling trials for the 1948 London Olympics and managed to qualify for the Games. His 18-day journey to London took him to Japan, Hong Kong, India, Egypt, and Italy, before arriving in London on 8 July. Once at the Games he competed in the road race, but did not finish the course. Hwang then spent more than a fortnight to get back home, travelling through the Netherlands, France, Italy, India, and Hong Kong. His journey to and from London also required him to be vaccinated against typhoid, tetanus, cholera, and plague.