Fans who attended Charlie Daniels' 40th annual Volunteer Jam in Nashville on Wednesday night (Aug. 12) got more than they bargained for when some surprise guests took the stage for unannounced performances.

The concert featured appearances from a diverse lineup of performers, including the Charlie Daniels Band, Ted Nugent, Trace Adkins, Alabama, Colt Ford, Lee Greenwood, the Oak Ridge Boys, Wynonna Judd, Craig Morgan, Travis Tritt and Montgomery Gentry, but it was the surprise guests that made the most waves, beginning with Southern country rockers Blackberry Smoke.

Eric Church was next on stage, joining fellow North Carolina native Daniels for a once-in-a-lifetime rendition of his patriotic hit, "In America." The performance marked the first time they have shared the stage.

Jamey Johnson also made a surprise guest appearance, and the evening wound up with Southern rock legends Lynyrd Skynyrd, who took the stage in the final hour of the concert for a set of hits that included classics like "Simple Man," "Sweet Home Alabama," "Gimme Three Steps" and "Free Bird."

Another high point of the evening was an emotional performance from Ryan Weaver, a veteran and former Blackhawk-pilot-turned-country-singer who paid tribute to his brother and brother-in-law, both lost in combat in Iraq, with a moving video.

The money raised from the event will benefit the Journey Home Project, which connects donors with organizations to address the healthcare, educational and career needs of veterans. Funds will also go to the Predators Foundation, which is devoted to "funneling the excitement of professional sports towards the needs of this community."

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