November 8th was the 40th anniversary of the release of Led Zeppelin IV, an album widely regarded as one of the best rock albums of all time. The album has sold upwards of 28 million units worldwide throughout its lifespan and houses such Zeppelin classics as 'Stairway to Heaven', 'Black Dog' and 'When The Levee Breaks'.
The album was a massive commercial and critical success immediately upon its release, debuting at #1 in the UK charts and staying in said charts for 62 weeks. It was ranked by Rolling Stone as the 66th best record ever made, by Mojo as the 24th, by Q as the 21st and by Classic Rock as the best rock record ever.