What year was the Indianapolis Motor Speedway built for car racing?

The Indianapolis Motor Speedway was officially built for car racing in 1909. This facility was constructed specifically to host automobile races, and it became the home of the Indianapolis 500, one of the most prestigious motor racing events in the world. The importance of this date in motorsport history is significant because it marked the establishment of one of the first purpose-built racetracks in the United States, designed to accommodate the growing automotive racing culture of the early 20th century.

The racetrack's design and construction reflected the need for a safe and controlled environment for car racing, which was becoming increasingly popular at the time. This makes 1909 a pivotal year in both the context of car racing and the overall development of motorsports in America.