Even in sound check, people at Circuit of the Americas know what they're about to see is special.

"Seeing Willie Nelson perform live, and seeing Kacey Musgraves perform live are kind of bucket list items for me, concerts I wanted to go to a long time," said Robert Brazelton.

The Salt Lake City, Utah-native truly did hit the road again, making the trek south to catch Nelson and a cast of other musical stars Tuesday during Willie's Picnic.

The "bucket list" theme was common throughout the crowd.

"It's my birthday… and Willie Nelson is on my bucket list," said Lisa Lowe, who was celebrating her birthday.

Willie's Picnic began back in 1973, and while the location has changed over the years, some things have managed to stay the same.

For one – you can always expect a who's who of music royalty on stage.

"Asleep at the Wheel, Steve Earle, Hayes Carll, - we came in right at the end of David Allen Coe. Just a bucket list of awesome performers all in one place," said Mike Pawlus, who came with friends.

While music naturally took center stage, nearly everybody was decked out in their red, white, and blue. Themes of pride and unity permeated throughout the air.

"I think Willie Nelson has a good track record and kind of reputation of bringing together a lot of different groups of people. So I like that there's as much diversity as there is because it kind of speaks to who he is as an artist. And not only his ability to bring people together, but everyone's willingness to come together and celebrate - not only him and his legacy, but also our country and everything that we stand for," said Brazelton.

"Willie Nelson almost embodies the kind of American spirit, all the trials that he's been through. He's still making awesome music - into his what, 80s? He's kind of just one of those guys that kind of signifies America, that spirit of freedom, and all that," said Pawlus.

For Brandon Boswell, the day had a little extra meaning.

"I'm on block leave, summer block leave - came home to see my family. They were like hey - want to come see Willie Nelson play? I was like 'hell yeah, that sounds great'," Boswell said.

A member of the Army, Boswell is set to deploy overseas next month.

"I'm very proud to serve my country," said Boswell.

He attended Tuesday with his family - his mother, proudly standing by his side throughout our conversation.

"He's our hero. It takes a brave man to join the military right now. That's my boy," said Vivian Boswell, as she embraced Brandon.

It's a reminder to honor all those who came before us and serve now - protecting the very freedoms we come together to celebrate on days like this.

"Every young soldier that has enlisted in the last -- what since 9/11 -- they deserve respect. This country is amazing because of them," Vivian Boswell said.