unsafe to the public as they offered relatively little crowd control. Promoters and drivers in the United States discovered that horse racing tracks could provide better conditions for drivers and spectators than public streets. This, in turn, was succeeded by board track racing (which was short-lived as many of the tracks were highly flammable and difficult to maintain) followed by oval track racing, which remains the dominant form of racing in the United States but is not used in the rest of the world; road racing has generally waned. However, an extensive, albeit illegal street racing culture still persists. IndyCar Series Historically, open wheel racing was the most popular form of U.S. motorsport nationwide. However, an acrimonious split (often referred to by many as "The Split") in 1994 between the primary series, CART (later known as Champ Car), and the owner of the Indianapolis Motor Speedway (the site of the Indy 500), Tony George, led to the formation of the Indy Racing League, now known as INDYCAR, which launched the rival IndyCar Series in 1996. From that point on, the popularity of open wheel racing in the U.S. declined dramatically. The feud was settled in 2008 with an agreement to merge the two series under the IndyCar banner, but enormous damage had already been done to the sport. Post-merger, IndyCar continues to run with slight viewership gains per year. However, as a result, the only post-Split IndyCar race that still enjoys widespread popularity among the general public is the Indianapolis 500. NASCAR The CART-IRL Split coincided with an enormous expansion of stock car racing, governed by NASCAR, from its past as a mostly regional circuit mainly followed in the Southern United States to a truly national sport. NASCAR's audience peaked in the early 2000s, and has declined quite a bit ever since the implementation of the Chase for the Cup in 2004, though it continues to have around 2–4 million viewers per race. Among NASCAR's popular former drivers are Jeff Gordon, Dale Earnhardt, Jimmie Johnson, Tony Stewart, Dale Earnhardt Jr., and Richard Petty. Among NASCAR's popular active drivers are Kevin Harvick, Alex Bowman, Kurt Busch, Kyle Busch, Chase Elliott, Ryan Blaney, and Kyle Larson. NASCAR's most popular race is the Daytona 500, the opening race of the season, held each year at Daytona Beach, Florida in February. Other motorsports Notable sports car races in the United States are the 24