The Chicago Marathon (branded Bank of America Chicago Marathon for sponsorship reasons and formerly the LaSalle Bank Chicago Marathon) is a major marathon held yearly in Chicago in Cook County, Illinois, United States. Alongside the Boston, New York, London, Berlin, and Tokyo Marathons, it is one of the six World Marathon Majors. Thus, it is also an IAAF Gold Label race. The October 13, 2013 running will be the 36th anniversary of the race. The first race was held on September 25, 1977 under the original name the Mayor Daley Marathon, which drew a field of 4,200 runners. The race has been held every year since, except in 1987 when only a half-marathon was run. It is among the fastest growing marathon road races in the world, due in part to its largely fast and flat course which facilitates the pursuit of personal records and world record performances. The race has achieved its elite status among marathons by developing relationship with sponsors who provide prize money to lure elite runners who have produced American and world record performances.