A glorious spring event following Patriots Day, the Boston Marathon has become something more than a 26.2-mile endurance race.
Everything changed in 2013, when two bombs exploded near the finish line. Three people died in the blasts and more than 260 were injured, a number of them losing limbs or having disfiguring injuries.
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In this era of terrorism, security everywhere is heightened. So it will be on April 20, the Monday running of the marathon from Hopkinton, Mass., to the finish line on Boylston Street in Boston.
There are new layers in the shadows surrounding the marathon, following the recent conviction of Dzhokhar Tsarnaev in connection with the bombing. The day after the marathon, jurors will begin consideration of whether Tsarnaev, 21, spends the rest of his life in prison or is executed.
But first, the marathon. Here's what you need to know.
IMAGES: Boston Marathon 2014
The Boston Marathon: This will be the 119th running of the race. The Boston Athletic Association began event management in 1897.
The course: On its way from Hopkinton to Boylston Street, competitors follow streets through Boston suburbs. Halfway point is in Wellesley.
(Courtesty Boston Athletic Association)
The most notorious place on the course is Heartbreak Hill, between miles 20 and 21. The rise is slight, but falls at a critical location in the race, a place where most runners "hit the wall."
Take a quick video tour of the race via The Boston Globe.
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Distance: 26 miles, 385 yards or 42.195 kilometers is the course covered by a Greek soldier Pheidippides, who carried word of victory over the Persians at the Battle of Marathon to Athens in 490 BC. The marathon was among the first Olympics events when the modern games began in 1896, although the distance was not formalized until 1921.
Participants: About 30,000 people take part in the race in its various sections. They are started according to qualifying criteria.
Start times: Staggered according to various factors listed here (all times ET). Mobility impaired: 8:50 a.m. Wheelchair Division: 9:17 a.m. Handcycle: 9:22 a.m. Elite women: 9:32 a.m. Elite men: 10 a.m. Wave 2: 10:25 a.m. Wave 3: 10:50 a.m. Wave 4: 11:15 a.m.
Winners: Meb Keflezighi, an American born in Eritrea, won in 2:08:37. He was the first American man to win since 1983. The 2014 race was run one week before his 39th birthday, making Keflezighi the oldest winner since 1930.
Rita Jeptoo of Kenya won her third Boston Marathon in 2014, in record time of 2:18:57.
Records: Kenya's Geoffrey Mutai holds the fastest time at 2:03:02 in 2011. Other records, according to The Boston Globe: men’s masters: John Campbell (New Zealand), 2:11:04 (set in 1990); women’s masters: Mary Hannah (United States), 2:27:58 (2012); men’s push rim wheelchair: Joshua Cassidy (Canada), 1:18:25 (2012); women’s push rim wheelchair: Jean Driscoll (United States), 1:34:22 (1994)
Learn more: Boston Athletic Association website (http://www.baa.org/); Boston Globe (http://www.boston.com/sports/marathon/)