The 2012 Boston Marathon took place in Boston, Massachusetts on Monday April 16, 2012. It was the 116th edition of the mass-participation marathon. Organized by the Boston Athletic Association, it was the first of the World Marathon Majors series to be held in 2012. A total of 22,426 runners started the race. The competition was held in hot running conditions, reaching 88 degrees Fahrenheit (31° Celsius) that afternoon, and some of the 27,000 registered runners opted to take up the organizers' offer to defer their entry until the 2013 race.