Most prog albums have at least one really long song, often spanning the entire side of an album. Jethro Tull's 1972 LP Thick As a Brick brought that trend to its logical conclusion: the entire album is just one song. Side one is "Thick As a Brick, Part I" and side two is (you guessed it) "Thick As a Brick, Part II." The two-part song lasts 44 minutes. The group's 1971 album Aqualung won them many new fans, and they took them on a pretty crazy ride with the follow-up. The group wasn't completely crazy – they allowed a three-minute radio version to be cut for radio. To many Tull fans, this album is Jethro Tull at their peak. In 2012, the group's frontman released a sequel to the album called Thick As a Brick 2, which follows the life of protagonist Gerald Bostock. It's likely this move didn't sit well with the others members of Jethro Tull. The band hasn't officially broken up, but they tour in separate camps now and appear to be over.