Athletes from all 50 states have descended on Lawrence for the K-Swiss Ironman 70.3 Kansas at Clinton State Park.

Nothing major has changed about today’s event — in its fourth year — but word is spreading about the uniqueness of the event on the Ironman series.

“It’s really neat to have all 50 states represented and put Lawrence on the map for one more thing,” race director Ryan Robinson said.

Athletes swim 1.2 miles, bike 56 miles and finish with a 13.1-mile run through Clinton State Park. Technically, it’s a half-Ironman event; a true Ironman is a 2.4-mile swim, 112-mile bike ride and 26.2-mile run.

Chrissie Wellington, the current women’s world record-holder at the full Ironman distance, will return to race for her third straight title.

“We feel pretty blessed to have her come to Lawrence,” Robinson said.

Wellington won last year’s event in a time of 4 hours, 7 minutes, 49 seconds, more than 16 minutes faster than the next woman.

“She’s amazing,” Robinson said. “I think Lawrence has really kind of adopted her, and she loves Lawrence.”

Chris Lieto, the male champion from last year, will not return this year. The winner from two years ago — Luke Bell from Australia — will participate.

Robinson said he expects 1,600 participants — and 1,000 volunteers — for the race.

“Lawrence has been great, and the state park is beautiful, so, yeah, everything is going well,” Robinson said.

This year, the race weekend at Clinton State Park kicked off Saturday with the Hy-Vee IronKids Triathlon, a shorter event for athletes ages 6-15.