As a poet, McGough came to national prominence through the publication of "The Mersey Sound" in 1967. "The Mersey Sound" is an anthology of poetry by three Liverpool poets: McGough, Brian Patten, and Adrian Henri. It went on to sell over 500,000 copies, becoming one of the bestselling poetry anthologies of all time; remaining in continuous publication, it was revised in 1983 and again in 2007. The title of the anthology was a conscious association of the three Liverpool poets with the musical phenomenon caused by the eruption of the Beatles and associated bands from the same city, known collectively as the "Merseybeat", on the world. McGough's personal connection with the Beatles was referenced in a much later comic poem, "To Macca's Trousers", contained in the book "That Awkward Age" (2009). McGough discovered a long forgotten pair of Paul McCartney's blue mohair trousers in his attic; the trousers had been given to him, via McCartney's brother Mike, in the early 1960s.