The bicentenary of John Snow's birth, a legend in his field, for his research on epidemiology and the prevention ofcholera, constitutes a unique opportunity to commemorate this iconic figure. In the article, his spectacular achievements in this discipline are presented, including his epidemiological investigation during cholera epidemic and the well-known Broad Street intervention in Soho, in 1854, as well as his methodologically elegant experiment "on the grandest scale" in which he compared the cholera fatality rates in households served by two different water supply companies. Having referred to Snow's research, the cholera outbreak in Haiti in 2010 is also discussed.