Even Wednesday's hot temperatures can't stop the fun at Country Jam USA. The country music festival begins Thursday in Eau Claire.

"It's been a very hot year. I mean I don't think I ever remember a year that was this hot and humid," Nick Mourn with Stage Pro Inc. said as he set up the stage.

With the sun beating down, hundreds of people set up the grounds. Despite the heat, the show must go on.

"We expect 75,000-90,000 people over the course of the weekend," Sandi Basley with Country Jam said.

With big name performers like Blake Shelton, Martina McBride and the Zac Brown Band, everything needs to be just right.

"Saturday night being the big huge night, Zac Brown and friends are pulling in a huge number of single day tickets," Basley said.

The stage is put up by the pros: people who set-up equipment like this all over the country.

"When we show up it is just a dirt parking lot. First thing we do, we build the stage and then the structure, which is the roof, which goes on top of everything," Mourn explained.

Those who have worked at Country Jam USA over the years say the stage set-up has gotten bigger and better.

"There's going to be millions of dollars of equipment up here," Mourn said.

After months of work, by hundreds of people, the country music festival will as big as ever.

“With Blake Shelton, Martina and Zac, you can't go wrong," Basley said.