A memorial to 2013 Boston Marathon bombing victim Martin Richard sits near the starting line of the 118th Boston Marathon (AP)

Kevin Brown, of Brockton, Mass., gets an early seat near the finish line to watch the running of the 118th Boston Marathon Monday, April 21, 2014 in Boston. Brown created the memorials to the 2013 bombing victims sitting near the the line, center rear. (AP Photo/Elise Amendola)

(USA TODAY Sports)

(USA TODAY Sports)

A couple embraces at the start of the Boston Marathon. (AP)

A runner with a temporary Boston Marathon tattoo gets ready at the start of the race. (Getty)

A couple huddles while waiting to load a bus to take them to the start of the Boston Marathon. (Getty)

Pepi Bolognese cleans the finish line before the running of the 118th Boston Marathon. (AP)

Mobility-impaired runners gather at the start line for a moment of silence before the 118th Boston Marathon. (AP)

The 118th Boston Marathon gets underway. (AP)