More than 3,500 runners are expected to run through the heart of the Scenic City in the third annual Chattanooga marathon. 

Organizers are expecting at least 5,000 visitors, including five USA Track and Field representatives. 

Chattanooga Sports Committee President, Tim Morgan says the group will be engaged in the Chattanooga Marathon, while also touring the Scenic City. Morgan hopes the opportunity puts Chattanooga in a better position to host the 2020 Team USA Marathon and Half-Marathon Olympic Trials.

"This was a part of the bid process but we invited them to be a part of this weekend that's so special to our community and so they could really see that we care more," said Morgan. "The people within this community are what will truly defined the success of the 2020 Olympics trials and we are are working to hopefully paint that portrait." 

Three other cities are on the list to host the trials. Morgan says Chattanooga's passionate running community, experience hosting large events, and scenic background stands out. Something Morgan says the Chattanooga Marathon provides all in one. 

But with a new two-loop running course, comes pressure in making sure everything measure out.     

"We have marked and remarked and our team once again will position the course according to our certification. We learned. We expanded on course assets and that corrected the problem. We still are reinvesting in our own course team to ensure that we are prepped and ready, according to the certified course," said Morgan. 

Registration for Sunday's marathon and half-marathon closed  Sunday at 7 p.m. To register, click here