Imagine six athletes riding bareback around a half-mile track at full speed, then jumping off, mounting a second horse, flying around the course, changing horses again and then rounding the track one more time.

It’s called Indian relay horse racing, and this summer it’s coming to the Remington Ranch in the Eau Claire County town of Union.

“The races are popular because they are so extreme,” said Marcus Red Thunder, race director for Extreme Thunder USA.

Billed as America’s oldest extreme sport, Indian relay horse racing is built around incredible horses, skilled riders and team members from Native American nations in the United States and Canada.

Indian relay horse racing involves a team of four: the rider, catcher, setup man and back holder.

Riders are fearless, agile athletes with amazing balance, stamina and strength, according to event organizers. They make three laps around the track, jumping off one horse and onto a new, fresh animal after each lap. This exchange is known as the “storm.”

Risking being run over by the incoming horse, the catcher waves down the rider as he gallops in for the exchange and catches the horse as the rider dismounts, sometimes having to use his body to stop a half-ton animal.

The setup man must keep the fresh horse calm and hold the animal until the rider mounts. This position requires split-second timing and skill at positioning the exchange horse so that the rider can have a clean setup and jump onto the horse.

The back holder, with a calm spirit and soothing words, keeps the third horse calm through the “storm” and then hands the animal over to the setup man.

Both fans of Indian relay horse racing, Larry Barr, who produces and builds music festivals, and Red Thunder, a native adviser for different tribes, decided to partner to bring a relay to Wisconsin.

“I think after people see it, it’s going to be the talk of the town,” Barr said. “It was something I thought was exciting enough to bring to Eau Claire.”

Extreme Thunder USA is inviting 48 Native American teams from around the United States and Canada to compete for $250,000 in prize money, said Red Thunder, who lives in Montana.

The event will kick off with Wednesday Family Fun Night from 4 to 8 p.m. Aug. 21. This isn’t a race day.

Eight races are planned from 6 to 9 p.m. Thursday, Aug. 22, to Saturday, Aug. 24, according to Extreme Thunder USA materials, with women’s and kids’ races planned between the fourth and fifth races of the day.

Indian relay horse racing “is the only extreme sport that involves the whole family,” Red Thunder said, noting teams consist of grandparents, parents, children and other family members.

In addition to racing, the event will include Native American music, dance and storytelling, arts and crafts and tours of a Native American village and teepees.

“It’s a perfect venue to teach our people and others that our culture is still alive, still going and still strong,” said Red Thunder, who is Ojibwe and Cree.

This spring, construction on the event site is set to begin at the Remington Ranch, owned by Bruce and Karen Remington and located about three miles from Country Jam.

No other event has a half-mile race track built specifically for Indian relay horse racing, Red Thunder said. The site outside of Eau Claire “is a first of its kind.”

The event is expected to draw 500 to 2,000 people on Aug. 21; 1,000 to 2,000, Aug. 22; 2,000 to 4,000, Aug. 23; and 3,000 to 5,000, Aug. 24, according to materials provided to Eau Claire County.

“It’s going to be something different,” said Bruce Remington, who has shared the coming event with people he knows. “The people who have heard about it are excited … .”

Contact: 715-830-5838, christena.obrien@ecpc.com, @CTOBrien on Twitter