The Iron Horse Bicycle Classic is one of the oldest organized bicycle races in North America. Cyclists compete with a steam train that runs between Durango and Silverton, Colorado.
The Iron Horse Bicycle Classic is one of the oldest organized bicycle races in North America. Cyclists compete with a steam train that runs between Durango and Silverton, Colorado.
David G. Allan/CNN
In 1972, Durango was looking for an event to kick off the summer tourist season. With just 36 cyclists that first year, the Iron Horse was born. It has run every Memorial Day weekend since.
In 1972, Durango was looking for an event to kick off the summer tourist season. With just 36 cyclists that first year, the Iron Horse was born. It has run every Memorial Day weekend since.
Scott DW Smith/Imagesmith/IHBC
While most riders leave at the same time as the train, about 30 minutes into the race, their paths diverge. Riders go over the mountains and the train stays down in the Animas River gorge, meeting again in Silverton.
While most riders leave at the same time as the train, about 30 minutes into the race, their paths diverge. Riders go over the mountains and the train stays down in the Animas River gorge, meeting again in Silverton.
Deborah Brunswick / CNN
Once a qualifying race for the Olympics, the Iron Horse Classic is now more popular than professional.
Once a qualifying race for the Olympics, the Iron Horse Classic is now more popular than professional.
David G. Allan/CNN
In 2016, one racer did the course on a large unicycle.
In 2016, one racer did the course on a large unicycle.
David G. Allan/CNN
The course is a spectacularly beautiful but grueling climb along a mountainous highway, going from 6,500 feet above sea level to 11,000 at its highest point.
The course is a spectacularly beautiful but grueling climb along a mountainous highway, going from 6,500 feet above sea level to 11,000 at its highest point.
David G. Allan/CNN
In 2016, 2,500 bicyclists came from 43 states and six countries. That number is the maximum allowed for safety reasons (in case they need to be evacuated for extreme weather).
In 2016, 2,500 bicyclists came from 43 states and six countries. That number is the maximum allowed for safety reasons (in case they need to be evacuated for extreme weather).
Scott DW Smith/Imagesmith/IHBC
Of the 2,500, 40 were professional-level racers and the rest seasoned amateurs.
Of the 2,500, 40 were professional-level racers and the rest seasoned amateurs.
Scott DW Smith/Imagesmith/IHBC
At the finish line in Silverton, riders are exhausted, their legs screaming for oxygen, but most look thrilled.
At the finish line in Silverton, riders are exhausted, their legs screaming for oxygen, but most look thrilled.
Scott DW Smith/Imagesmith/IHBC
Every year, about 30% of the cyclists beat the train, which takes 3½ hours to reach Silverton.
Every year, about 30% of the cyclists beat the train, which takes 3½ hours to reach Silverton.
David G. Allan/CNN
The semi-kitschy, mountain-rimmed Old West town of Silverton turns into party of music, beer and congenial bragging.
The semi-kitschy, mountain-rimmed Old West town of Silverton turns into party of music, beer and congenial bragging.
David G. Allan/CNN
A live oompah band and a Memorial Day ceremony were part of the 2016 celebrations.
A live oompah band and a Memorial Day ceremony were part of the 2016 celebrations.
Scott DW Smith/Imagesmith/IHBC
The town is taken over by happy competitors and their supporters for several hours before buses, the train and box trucks full of bikes take the party back to Durango.
The town is taken over by happy competitors and their supporters for several hours before buses, the train and box trucks full of bikes take the party back to Durango.
Scott DW Smith/Imagesmith/IHBC
Racers compete in the Iron Horse for the prestige and the race's unique history. It's a life experience for the bucket list.
Racers compete in the Iron Horse for the prestige and the race's unique history. It's a life experience for the bucket list.
Scott DW Smith/Imagesmith/IHBC