On Wednesday afternoon, Rascal Flatts gathered with friends and family to Nashville's Hard Rock Cafe on Lower Broadway, where they celebrated the success of their latest chart-topping hit, 'I Won't Let Go.' Also on hand for the celebration was the Flatts' record label, Big Machine Records, and one of the song's writers, Jason Sellers, who co-wrote the tune with Steve Robson (Sellers is pictured above with Rascal Flatts and Big Machine President/CEO Scott Borchetta).

When 'I Won't Let Go' topped the country singles chart, the hot trio locked in another career hit, giving them a grand total of 13 No. 1 singles to date. In the midst of the celebration for the song, the band was also surprised with the news that their debut album released on Big Machine Records, 'Nothing Like This,' had reached record sales of one million copies.

"With God's help, we have been able to bring together a wonderful group of people to surround and reinvigorate our career," Rascal Flatts' Jay DeMarcus said during the party. "We are living a dream come true."

Rascal Flatts are currently on the road in the midst of their Flatts Fest Tour, also featuring Sara Evans, Justin Moore and Easton Corbin. Click here for a complete list of dates where the tour will be stopping.

Watch Rascal Flatts Perform 'I Won't Let Go'