circuit and race tracks. These cars are heavily based on technology and their aerodynamics. The speed record was set in 2005 by Juan Pablo Montoya hitting 373 km/h (232 mph). Some of the most prominent races are the Monaco Grand Prix, the Italian Grand Prix, and the British Grand Prix. The season ends with the crowning of the World Championship for drivers and constructors. In the United States, the most popular series is the IndyCar Series. The cars have traditionally been similar to, though less technologically sophisticated than, F1 cars, with more restrictions on technology aimed at controlling costs. While these cars are not as technologically advanced, they are faster, mainly because they compete on oval race tracks, being able to average a lap at 388 km/h (241 mph). The series' biggest race is the Indianapolis 500, which is commonly referred to as "The Greatest Spectacle in Racing" due to being the longest continuously run race and having the largest crowd for a single-day sporting event (350,000+). The other major international single-seater racing series is Formula 2 (formerly known as Formula 3000 and GP2 Series). Regional series include Super Formula and Formula V6 Asia (specifically in Asia), Formula Renault 3.5 (also known as the World Series by Renault, succession series of World Series by Nissan), Formula Three, Formula Palmer Audi and Formula Atlantic. In 2009, the FIA Formula Two Championship brought about the revival of the F2 series. Domestic, or country-specific, series include Formula Three and Formula Renault, with the leading introductory series being Formula Ford. Single-seater racing is not limited merely to professional teams and drivers. There exist many amateur racing clubs. In the UK, the major club series are the Monoposto Racing Club, BRSCC F3 (Formerly ClubF3, formerly ARP F3), Formula Vee and Club Formula Ford. Each series caters to a section of the market, with some primarily providing low-cost racing, while others aim for an authentic experience using the same regulations as the professional series (BRSCC F3). There are other categories of single-seater racing, including kart racing, which employs a small, low-cost machine on small tracks. Many of the current top drivers began their careers in karts. Formula Ford represents the most popular first open-wheel category for up-and-coming drivers stepping up from karts. The series is still the preferred option, as it has introduced an aero package and slicks, allowing the junior drivers to gain experience in