Ironman triathlons take place throughout the year around the world, including in Sweden, Denmark and the United States.
Athletes will begin the Leeds event in Roundhay Park with a 2.4-mile lake swim.
They will then embark on a 112-mile bike course up into the Yorkshire Dales National Park, with approximately 2,500m elevation gain.
Finally, athletes will take on a 26.2-mile run on a multi-lap course around Roundhay Park before reaching the finish line.
Organisers are advising residents and commuters to allow extra travel time and check their routes before setting off.
