Rita Jeptoo of Kenya crosses the finish line to win the Women's Elite division of the 118th Boston Marathon on April 21. Timothy Clary /AFP/Getty Images hide caption

itoggle caption Timothy Clary /AFP/Getty Images

Kenya's Dennis Kimetto crosses the finish line to win the Berlin Marathon Sunday. Kimetto set a new world marathon record, breaking the 2 hour, 3 minute mark for the first time. Tobias Schwarz/AFP/Getty Images hide caption

itoggle caption Tobias Schwarz/AFP/Getty Images

Carol Downing is still haunted by memories of last year's marathon. But she's excited about reuniting with other survivors. Michael Dwyer/AP hide caption

itoggle caption Michael Dwyer/AP