Horses, riders and runners crossed three streams in the course of their 22-mile race through the hills of central Wales. The average finish time was the same for both species — four hours. Ryan Kellman and Adam Cole/NPR's Skunk Bear hide caption

itoggle caption Ryan Kellman and Adam Cole/NPR's Skunk Bear

Harriette Thompson, 92, and her son Brenny Thompson finish the Suja Rock 'n' Roll San Diego Marathon on May 31 in San Diego. Jerod Harris/Getty Images for Rock 'n' Roll Marathon Series hide caption

itoggle caption Jerod Harris/Getty Images for Rock 'n' Roll Marathon Series

Haneen Radi, an Arab Israeli, wants to organize a marathon for her town of Tira, but was told the run couldn't include women. When she insisted, she received threats, and the back window of her car was shot out. Emily Harris/NPR hide caption

itoggle caption Emily Harris/NPR

Kenya's Eliud Kipchoge (left) celebrates winning the London Marathon next to runner-up and last year's winner Wilson Kipsang, also of Kenya, on Sunday. Facundo Arrozabalaga/EPA/Landov hide caption

itoggle caption Facundo Arrozabalaga/EPA/Landov

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