A young fan waits for participants to line up in Hopkinton.

Boston Marathon champion Joan Benoit Samuelson warmed up prior to the start of the 117th running of the Boston Marathon, in Hopkinton.

Volunteers Rich Storrs, Dottie Page , and Leslie Delmonaco (pictured left to right) stood on the starting line before the start of the 117th Boston Marathon in Hopkinton.

Defending champion Joshua Cassidy, of Canada, fifth front right, startws the wheelchair division of the 117th running of the Boston Marathon.

John Young of Salem started the Mobility Impaired Program.

The first wave of runners raced across the start line after the Elite Men started at 10:00 AM.

The crowd of runners signaled the race was underway.

Participants started in the elite men's division of the race.

Defending champion Wesley Korir, of Kenya, warmed up prior to the start of the race.

Bob Giese of Concord stretched his calves at the start in Hopkinton. Many runners warmed up with stretches and short sprints to counter the cool morning temperatures.

Bob Giese of Concord stretched his calves. Many runners warmed up with stretches and short sprints to counter the cool morning temperature.

Fred Aleck out of Worcester will skate the marathon for the 27th year. He spoke to Boston.com’s Steve Silva about his yearly challenge.

The start line swarmed with cyclists who rode the marathon route backwards to get to Hopkinton. They will head back to Boston for their second round of 26.2 miles for the day.

Race staff and volunteers anticipated the runners’ arrival.

Massachusetts Army National Guard soldiers began their march of the race path around 7a.m.

Race director Dave McGillivray told Boston.com’s Steve Silva, “It’s great that all of the qualified runners coexist with those who run for charities.”

Boston.com producer Julie Balise geared up to run the marathon. She set up a phone reminder about race day ... in case she forgot.

Dick Hoyt (left) and his son, Rick, posed for photos by the statue bearing their images at the start point in Hopkinton.

Tranist police gathered at the start point .

David Chapin Jr., 26, of Natick, had his father David Chapin Sr. apply a heating pad to his back before the start of the race. Chapin has run the marathon eight straight times. He has a metal rod in his back due to scoliosis.

After raising $250,000, the Patriots’ Charitable Foundation team gathered at the starting line and were ready to go.

"Unofficial" runners Joe Beyer,50, of Concord, Arnie James,69, of Somerville, and Tony Ong, 40, of Andover, rested before the start of the race.

Tracy Ellsworth of Lynnfield put on a blister pad in the Masonic Hall in downtown Hopkinton before the race. Ellsworth an os part of the Children's Hospital team.

Ray Phillips of Acton slept in the Masonic Hall in downtown Hopkinton before the race.