UPDATE: Walker County will be affected by the Ironman 70.3 competition Sunday as the bike course runs through the county. 

Residents are encouraged to review the areas that will be impacted while cyclists trek through an area awarded the 2017 Athletes Choice Award for Best Overall Bike course in 2017.

The race begins at 6:50 a.m. in Chattanooga, but race organizers warn roads in Walker County along the course could encounter delays between 5 a.m. and 1 p.m. The areas at greatest risk of delays are Hwy. 193 at Hwy. 341, Hwy. 136 at Hwy. 193 and Hwy. 136 at Hwy. 341.

PREVIOUS STORY: Road closures are underway as Chattanooga prepares for another Ironman 70.3.

Thousands of athletes are coming to our area for Sunday's 8.5 hour triathlon.

This year, Ironman has a way you can navigate the area even if you aren't competing.

"We're coming into our 5th year with associating our community with this brand," Chattanooga Sports Committee President Tim Morgan said.

Three thousand athletes from around the world will be in Chattanooga this weekend for Ironman 70.3.

The Scenic City is expected to rake in $4-million from athletes, spectators and volunteers this weekend alone.

"They try to have a minimal impact on our community while maximizing the economic impact on Chattanooga," Morgan added.

Ironman is trying to make it easier to get around town whether you're here for the event or trying to navigate the area through the Ironman app.

"That'll show you where the swim, bike run is and it'll show you what roads will be utilized and they won't be completely closed, but there will be delays," Morgan said.

A full Ironman competition is set for September.