The Red Bull Trans-Siberian Extreme is the longest bicycle road race in the world, a grueling endurance test of 14 stages that unfurl over 5,700 miles from Moscow to Vladivostok.

The distance is so great that riders pass through seven time zones. They roll over roads through forested hills, along highways clogged with trucks. They spin along pavement, cobblestone and gravel, and through meadows as vast as the eye can see.

For this year’s race, eight men and two women set off from Moscow’s Red Square on July 18. They have dropped out one by one, and by Monday, there were just three remaining: Pierre Bischoff of Germany, Aleksey Shchebelin of Russia, and Marcelo Soares of Brazil. On Wednesday, these three will begin the 14th and final stage, pushing to be the first to roll up in front of the opera house in Vladivostok, a port city near the border with China, on Aug. 14.