Led Zeppelin launched a UK "thank you" tour on March 5th, 1971, booking shows at their earliest haunts and charging original 1968 admission prices! Zeppelin expressed their gratitude by premiering songs from their upcoming studio album, Led Zeppelin IV, performing the now legendary "Black Dog", "Going to California" and "Stairway to Heaven". Led Zeppelin IV went on to become one of the best selling albums, moving 32 million units world wide! The album is certified 23x platinum and is the 3rd best selling album ever in the US! Classic Rock Magazine bestowed the title "Greatest Rock Album Ever" on IV in 2001! Click here to check out Led Zeppelin on iTunes!