Today marks the 50th anniversary of the release of Jethro Tull‘s classic album Aqualung, which features some of the eclectic British rock band’s most enduring songs, including the title track, “Locomotive Breath,” “Hymn 43” and “Cross-Eyed Mary.”

Aqualung, Jethro Tull’s fourth studio effort, peaked at #7 on the Billboard 200, and is the group’s all-time best-selling record, having sold over 3 million in the U.S.

The album kicks off with the title track, a dynamic, riff-heavy song about an unsavory street person.

Jethro Tull frontman Ian Anderson tells ABC Audio that the song was inspired by a photo of a London homeless man taken by his then-wife Jennie, who also co-wrote the lyrics.

As Anderson recalls, “It was the humanity and the sadness, the vulnerability of this person that made me say…’Let’s write a song about this character. Let’s imagine who he is. Whether he has a name. What does he do? Where does he live?’ But more importantly, it’s not just about him. It’s about our reaction to the homeless. Our feelings of compassion, of fear, of discomfort, of sometimes disdain.”

Meanwhile, Ian says the Aqualung album “is defined by that song, in the sense of drama and the sense of dynamic variation between loud and quiet, and slow and fast.”

While Aqualung often is labeled a concept album, Anderson insists it isn’t, although, as he notes, the record is split into two thematic sides. The first features “whimsical social documentary pieces” such as the title track and “Cross-Eyed Mary,” while the second showcases “religious commentary songs” like “My God” and “Hymn 43.”

Anderson will celebrate the album’s anniversary by taking part in a livestream event starting at 1 p.m. ET at Jethro Tull’s YouTube channel.

Here’s the Aqualung track list:

Side One: Aqualung
“Aqualung”
“Cross-Eyed Mary”
“Cheap Day Return”
“Mother Goose”
“Wond’ring Aloud”
“Up to Me”

Side Two: My God
“My God”
“Hymn 43”
“Slipstream”
“Locomotive Breath”
“Wind-Up”

By Matt Friedlander
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