Most of the recording sessions for Metallica's The Black Album were held in Los Angeles.
The band recorded primarily at One on One Recording Studios in Los Angeles, where sessions ran from October 1990 through June 1991. The location became the main setting for the album's demanding production period with Bob Rock.
Metallica also recorded for about a week at Little Mountain Sound Studios in Vancouver, Canada, and later completed additional overdubs and mixing at A&M Studios in Hollywood. Those extra locations can cause confusion about the album's main recording city.
The sessions were unusually collaborative for the band. Rock encouraged the members to play together in the studio, and the production team captured numerous takes before editing the strongest performances into the finished tracks.