Barry Lyndon received Academy Awards for Best Art Direction, Best Cinematography, Best Costume Design and Best Musical Score. Kubrick was nominated three times, for Best Director, Best Picture, and Best Adapted Screenplay. Its Scorsese's favourite film, its Brian Eno's favourite film. It is renowned for its cinematography, its music is fantastic, the Prussian War battlefield shots are superb too.
Agree about O'Neal though. He was wank.