Two of the songs, "Master James of St. George" and "Victorian Brickwork", are about Spawton's father, who died shortly before the album was released.

The 23 minute title track, "The Underfall Yard", is a song about Isambard Kingdom Brunel and the great Victorian engineers.

The Underfall Yard itself is located in Bristol and is an engineering solution, partly developed by Brunel, to maintain water and silt levels in the city's harbour.

In the book, Fortey describes a journey along Brunel's Great Western line, where, as the author travelled west, the rocks are found to be older.

The album was remixed and reissued as a double CD and three-LP set in April 2021 and features new studio re-recordings of "Victorian Brickwork" and "The Underfall Yard", along with a new brass arranged prelude to the title track and the brand new song "Brew and Burgh".