Metallica [ tickets ] will warm up for the upcoming Summer Sanitarium tour--which also features Limp Bizkit [ tickets ], Linkin Park [ tickets ], Deftones [ tickets ] and Mudvayne [ tickets ]--by playing four free concerts at the Fillmore in San Francisco.

Bay Area-based Metallica is set to play the hometown gigs on May 18, 19, 21 and 22, according to the band's official website. Tickets will be awarded via a fan-club drawing, and radio stations will also give away tickets.

"St. Anger," Metallica's first album with new bass player Robert Trujillo, is scheduled for release on June 10. Former Ozzy Osbourne bassist Trujillo and former Metallica bassist Jason Newsted have switched positions.

"[Metallica has] a lot of practicing to do, what with not touring in almost three years, and with the new brother in town, they need to get their act together... it's going to take four nights," said a posting on the band's website.

Metallica has also announced that it will play three club shows in a single day on June 11 in Paris.

The Summer Sanitarium tour is scheduled to open in the Detroit area on July 4.

On May 6, MTV will air a new 90-minute edition of "MTVIcon." During the program--which will be taped on May 3 before a live audience in Los Angeles--Avril Lavigne, Korn, Limp Bizkit and Sum 41 will be among the acts to perform their renditions of some classic Metallica songs.