"We were well over 950 runners when we left the building (Tuesday)," Donna Gale, Joliet Park District Special Events Coordinator said. "We expect it to be around 1,000."
In 2008, the race had 500 participants. In 2009, 620 and in 2010, 975.
Gale said the race is popular for a couple reasons.
"One is the beautiful, scenic Pilcher Park," Gale said. "We also have a cookout afterwards which is somewhat unusual."
The race was gaining steadily in popularity and significantly gained ground after the Joliet Park District combined it with two other races to create the Run 3 series.
Each year, runners can register for the Rockdale Ramblin' Run, which is a 10K held in April and the Redeye Run, which is an 8K held in November. Each of the three runs has a unique draw, with a cookout to wrap up the Sundowner and bloody Marys to greet runners at the end of the Redeye.
Race organizers have capped the participant limit at 1,200. Registration will be accepted on site, but Gale suggests arriving early.
"I would suggest getting there by 5:30 p.m., which is when race day registration starts," she said.
Registration closes at 6:45 p.m.
The Sundowner is always held at the end of July and Gale said runners have to be careful to hydrate.
"If you're planning on running it, July is always going to be hot, you need to hydrate all day long and take advantage of the water we are passing out," she said.