The Backstreet Boys celebrated the 20th anniversary of their classic song, "I Want It That Way" this weekend.

The song came out on April 12, 1999.

"20 years of I Want It That Way and 3x platinum @RIAA certified digital single... can't thank you guys enough for keeping the Backstreet pride alive! #IWantItThatWay20," the group's Twitter feed said Saturday.

A day earlier, the "Millennium 20 Edition" of the music video for the song was posted on YouTube.

It is the original music video with printed trivia blurbs and quoted memories from band members Nick Carter, Kevin Richardson, Brian Littrell, Howie Dorough and A.J. McLean popping up throughout.

The Backstreet Boys announced their DNA concert tour in November.

The group is scheduled to kick off the North American leg on July 12 in Washington, D.C., and will wrap it up Sept. 15 in Newark, N.J.