Sgt. Pepper's Lonely Hearts Club Band — The Beatles (1967)

Released in June 1967, the Beatles' eighth studio album spent 27 weeks at #1 in the UK and is the best-selling album in British history with 32 million copies sold. Critic Robert Christgau called it the album that 'changed everything' — from its gatefold sleeve to its orchestral overdubs, it established the concept album as rock's highest art form.