TULSA, Oklahoma - The course for this year's Tulsa Run is changing, all because of an upcoming $350-million park project.

Construction of The Gathering Place is expected to close the main part of the race course which is usually Riverside Drive, but now the run will make some turns through midtown to avoid the closure.

The Tulsa Sports Commission released a new map of the course Monday morning.  

See a map of the new course on TulsaSports.org.

The race will still start at 6th and Boulder and end at 4th and Boston.  But because "The Gathering Place" construction which is expected to start sometime this fall, Tulsa's oldest road race will change course.

The new 9.3-mile course is going to be hilly and test some of the fittest runners around; and for drivers, the new course means the roads you once used to avoid the race will now be closed.

Bobby Bomer is a long time runner of Tulsa's oldest road race. He finished his first Tulsa Run back in 1979 and he still has the shirt to prove it.

Bomer and his fellow runners are getting their first look at this year's course map that takes them on a new path.

"This new course that I saw is going to be a real challenge. I think it's maybe the toughest course we've had to date,” Bomer said.

Anticipated construction at The Gathering Place along Riverside Drive is why race officials had to make a new course map this year.

"Normally we would do an 'out and back' on Riverside that would take up a large portion of our run, so now we're going to btravelingng more of Midtown,” said Race Director, Heath Aucoin.

At Monday's kickoff event, Aucoin unveiled the new course map. The flatter Riverside Drive will be replaced with the rolling hills of midtown, where runners make the climb through Cherry Street.

Instead of hugging the Arkansas River, runners will make their way down to the hillier portions of Peoria.

This new course is something runners will have to prepare for. Bomer said runners will have to learn how to maximize their endurance on the hilly course.

"Those that go out too fast, they're going to have a long day,” Bomer said. "It's rolling hills you get to run down. If you understand racing and you run downhill right, and you don't burn too much energy running uphill, and then you'll do fine,"

Aucoin expects blocked off roads in midtown to open up as runners get closer to the finish line.

"Riverside really didn't affect much traffic, so now we're going to be doing rolling road blocks and we kind of separated the race out, so we're trying to spread it out so the traffic can go through and we won't affect traffic as much," Aucoin said.

Expect the main 15k course to be closed from nine to noon on race day, October 25th.