Eliud Kipchoge, the two-time Olympic gold medalist and marathon world record holder, is making his Boston Marathon debut and is the favorite in the elite men's race.

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The 127th running of the Boston Marathon is also the 10-year anniversary of the double bombings near the finish line that killed three people and injured at least 264.

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Lelisa Desisa, who won the men's race in 2013 and donated his medal to the city, returns to Boston along with two other previous champions - Kenyans Evans Chebet and Benson Kipruto.

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The Boston Marathon is a point-to-point course, which is not eligible for a world record due to its hills and windy conditions.

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Kipchoge's world record of 2:01:09, set at last year's Berlin Marathon, is unlikely to be broken at Boston, but Geoffrey Mutai's course record of 2:03:02 from 2011 is a target for him.

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Kipchoge has been training on a hilly course near his training base in the Kenyan village of Kaptagat, specifically designed to replicate the undulations of the challenging Boston course.

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The women's elite race will be headlined by three former Boston winners: Des Linden, Edna Kiplagat, and Atsede Bayisa.

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Close to 30,000 athletes from more than 100 countries will take part in this year Boston Marathon, including Sara Hall who owns the fastest time of 2:20:32 among the American women in the elite field

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The course is net downhill but includes four notable climbs in the second half culminating with the notorious Heartbreak Hill at the 20 mile mark make it a technical course compared to other marathons

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The weather could play a crucial role at the Boston Marathon, with rain and wind forecast during the day, which could make it more challenging for the runners.

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