After 26 seconds of silence to honor the victims of the Sandy Hook Elementary School shooting , the marathon got underway with 52 wheelchair competitors leaving Hopkinton at 9:17 am EDT . At 9:30 am , 51 elite women left the starting line , followed by the elite men at 10 am . The remaining competitors were released in three waves over the next 40 minutes . In total , 23,336 competitors , from all 50 states plus Washington D.C. and Puerto Rico , and from 92 countries , started the marathon . The temperature at start time was in the upper 40s °F ( 8 &ndash; 10 °C ) range and climbed to at the finish
Sandy Hook Elementary School shooting
Sandy Hook Elementary School shooting
2013 Boston Marathon