TULSA, Oklahoma - A Tulsa Labor Day tradition continues to grow as thousands of people watched and participated in the fourth annual Great Raft Race.

Shortly after 8 a.m., the first raft was launched from the boat ramp in Sand Springs. It, along with around 150 rafts, took part in the annual event.

The starting line was at the Case Community Park in Sand Springs. From there, the rafts made their way down the Arkansas River to the finish line at West Festival Park in Tulsa. Organizers said it takes about four hours to float to the finish line.

Joe Sullivan is visiting family from San Diego and decided to build a raft this year with his crew.

"We're the shirt clan and we've been together since 1988, and every year we do an experience with each other in Utah, Colorado, Missouri, Arkansas," Sullivan said.

And this year, Tulsa.

Sullivan’s cousin, Sydney Wright, worked behind the scenes to get the raft seaworthy.

"We took it out last weekend to make sure it would float, and it did,” Wright said.

With four years in the books after bringing the race back to town after being gone for decades, volunteers like Tanner Sturm said they couldn't be happier with how the event has grown and how successful it is.

“It’s Labor Day, and people want to be in the water and having fun with their families, and we want this to be on their yearly calendar to do that on their Labor Day,” he said.

Volunteers said the crowd started to show up several hours earlier than normal as the event's popularity continues to grow. They even changed the layout to provide more space for games and food trucks.

"We've just grown every year. We've figured out better processes and how to make the event better, and I think it's exciting to see that momentum," Sturm said. “That anxiety about can we make it happen, and I think because of all the passion and determination, that is what has really carried it, and now we have to keep it up because it has become popular.”

The race began in 1973 and ran until 1991, and, at its peak, there were 600 rafts, 4,500 racers, and 150,000 spectators that lined up along the Arkansas River.

The race resumed in 2015.