Is the Marathon Wall Finally Dead?

June 26, 2026

Over the course of one week in April, Kenyans John Korir and Sabastian Sawe rewrote what was possible in running’s ultimate distance. It began on Marathon Monday in Boston, where the 29-year-old Korir, from Eldoret, took advantage of cool conditions and a friendly tailwind to obliterate the Boston Marathon course record by running 2:01:52. Six days later in London, the 31-year-old Sawe, from Kapsabet, clocked 1:59:30 to take more than a minute off the world record and become the first man to break two hours in an official marathon.

The numbers behind Korir and Sawe’s runs were dazzling. Both men ran significant negative splits. After hitting halfway in 61:50, Korir ran Boston’s second half, which includes the fabled Newton Hills, in 60:02. Sawe went even faster in London, running his second half in 59:01 — easily the fastest half ever in any marathon — and splitting 13:42 for the 5k segment from 35-40k (1:55:37 marathon pace) with a gentle tailwind behind him. LETSRUN.COM