Chicago [ tickets ] and Earth, Wind & Fire [ tickets ] will join forces again for a two-month summer tour, the first time the two acts have set out together since 2005.

The tour, which will feature both bands playing separate sets of their own material, then joining at the end of the evening to share the stage for a third set, kicks off June 5 in Orange Beach, AL. The 30-city outing is slated to run through early August; details are included below.

The two bands--both staples on the classic rock circuit for decades--initially toured together in 2004, with a platinum-selling DVD, "Chicago/EWF: Live at the Greek Theatre," surfacing the following year. The groups repeated the shared road trip the in 2005.

Last year, Chicago celebrated its 40th anniversary as a group by releasing "The Best of Chicago: 40th Anniversary Edition," a career-spanning collection comprising 38 songs on two discs. The set, which covers music from the band's 1969 debut, "Chicago Transit Authority," to 2006's "Chicago XXX," contains 30 Top 40 radio tracks, including No. 1 hits "Look Away," "Hard to Say I'm Sorry" and the Grammy-winning "If You Leave Me Now."

Also last year, Rhino Records finally released the band's long-delayed 1994 album, "Stone of Sisyphus." Recorded in 1993 with producer Peter Wolf (J. Geils Band), the album sat on the shelf for 15 years after the band's then-current record company reportedly dismissed the set as "unlistenable."

The band's most recently recorded set, 2006's "Chicago XXX," marked its 30th album and its first collection of new material in 10 years. The record was produced by Rascal Flatts member Jay DeMarcus.

During its long career, Chicago has sold more than 120 million records, landed five consecutive No. 1 albums and racked up 50 hits in the US, including five No. 1 singles.

Earth, Wind & Fire's most recent studio set, "Illumination," hit stores in 2005, marking the band's 35th year together and representing the group's 23rd studio album. The disc, which scored the highest debut of the band's history, features songs produced by Raphael Saadiq, Black Eyed Peas leader Will.I.Am, Organized Noise, Brian McKnight and the team of Jimmy Jam and Terry Lewis. Guest performers include Saadiq, Will.I.Am, McKnight, Big Boi of OutKast, Kenny G, Floetry and Kelly Rowland of Destiny's Child.

The group's founding members--Maurice White, Phillip Bailey, Verdine White, Ralph Johnson, Al McKay, Larry Dunn, Andrew Woofolk, Fred White and Johnny Graham--were inducted into the Rock and Roll Hall of Fame in 2000. Last month, the band, reportedly a favorite of President Barack Obama, performed at the White House during the first social event hosted by the Obama Administration.