The Boston Marathon is an annual marathon hosted by several cities in greater Boston in eastern Massachusetts, United States. It is always held on Patriots' Day, the third Monday of April. It began in 1897, inspired by the success of the first marathon competition in the 1896 Summer Olympics.

On April 19, 1897, ten years after the establishment of the Boston Athletics Association (B.A.A.), the association held the 24.5 miles (39.4 km) marathon to conclude its athletic competition, the B.A.A. Games. The inaugural winner was John McDermott, who ran the 24.5 mile course in 2:55:10, leading a field of 15. The event was scheduled for the recently established holiday of Patriots' Day, with the race linking the Athenian and American struggles for liberty. The race, which became known as the Boston Marathon, has been held every year since then, even during the World War years, making it the world's oldest annual marathon.

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