Metrication in the United States traditional mile-based lengths. In the Olympics, athletes run 1500 meters, not 1600 meters. Running races in the U.S. are usually run in metric distances (e.g., the 100 metres dash or the 5K run), although the mile distance remains popular. But even 5 and 10 kilometer races most often have mile markers on the course, and no kilometer markers. Long-distance races are often measured in kilometers, although exceptions exist (generally 10 mile races). The marathon is referred to as a 26.219-mile race (the official marathon standard distance originally being in English units — 26 miles, 385 yards) rather than 42.195 km.
Athletics at the 1908 Summer Olympics – Men's marathon at the Olympic Stadium, the Great White City Stadium in Shepherd's Bush in London. The Polytechnic Harriers were also tasked with organising a Marathon Trial Race, to be run along most of the Olympic Marathon route. By April 1908, a revised map of the course of the Trial Race was published, also showing the intended course of the Olympic Marathon. It had by this time been decided to fix the Olympic Marathon distance at "about 26 miles" to the stadium, plus a lap of the track (), using the Royal Entrance as the marathon tunnel, and finishing at the normal