John Surtees is the only person to win world championships on both two wheels and four wheels.
Surtees first conquered motorcycle Grand Prix racing, winning seven world titles for MV Agusta. Four of those championships came in the premier 500cc class, while the others came in the 350cc category. His motorcycle success made him one of the dominant riders of the 1950s.
He then switched to cars and joined Ferrari in Formula One. In 1964, Surtees won the Formula One World Drivers’ Championship after victories in Germany and Italy helped him defeat Graham Hill by a single point. That achievement made him unique across the two major forms of world championship racing.
A common mix-up is Graham Hill, who won Formula One titles and the Indianapolis 500, but not a motorcycle world championship. Mike Hailwood was another legendary motorcycle champion who competed in Formula One, yet he never won the F1 title. Surtees also later founded his own racing organisation, which competed in several formula categories.