Blue Note Records has some of the best designed album jackets ever. The Reid Miles-designed covers of the 50s and 60s are particularly stunning and used label co-founder Francis Wolff's photos to great effect.
The label was formed in 1939 and is still operating today. Check out these covers — they're all gorgeous —
A number of them I'd even call iconic (Una Mas, No Room for Squares, Evolution, Smoke Stack, Idle Moments, My Point of View...). Unbelievably, all of the above are from just one year: 1963 — and they're not even all of the '63 covers!
A complete timeline of Blue Note Records album covers is available on the label's website.