The first time he worked alongside a Cliff it caused a sensation.
Now, over two decades later, Van Morrison (67), is causing a stir with his upcoming concerts featuring an altogether different kind of cliff.
Next month's north coast gigs will be a far cry from when Cliff Richard and the east Belfast singer-songwriter teamed up to perform Whenever God Shines His Light on Top of the Pops in 1989.
Those behind Van Morrison's special shows at Dunluce Castle have admitted they face a "mammoth" task behind the scenes to ensure all runs smoothly ahead of the shows.
Morrison will bring his musical magic to the stunning 700-year-old castle on June 7 and 8.
Around 1,000 tickets have been released for the intimate gig, with Van 'The Man' Morrison performing on a stage perched on cliffs more than 200ft above the north Atlantic ocean.
Dunluce Castle has been the scene of countless bloody battles and sieges throughout its colourful history but it will be the first time its walls have reverberated with the sounds of a concert.
Rather than face-off blood-thirsty invaders, the current custodians as well as the concert organisers must overcome the logistics of accommodating hundreds of revellers gathered yards from the north coast's stunning but precarious drop.
Screens will be erected along the cliff-edges, with a tough balancing act to overcome, ensuring they don't obscure the stunning scenery.
Over 100 technical staff will descend on the site in the days ahead of the Solstice at Dunluce festival, erecting a range of state-of-the-art lights designed to showcase Dunluce in all its glory, the first time the castle has been lit up.
Dunluce Castle belongs to the McDonnell family, who also own Glenarm Castle in Co Antrim.
Nigel Campbell, from Glenarm Castle, is overseeing the project along with Exile Promotions and admitted the challenges posed are "mammoth" but is confident the results "will be phenomenal".
"When we do concerts on an estate it is a lot different because the infrastructure is there," Mr Campbell told the Belfast Telegraph.
"Things are pre-built for the occasion so we don't have much to do for it. Something like this at Dunluce is a different story because you are taking a site on the edge of a cliff with no shelter and turning it into a concert venue."
The organisers initially wanted to stage the concert within the castle boundaries but this had to be changed due to ongoing archaeological work.
The concert will take place on land adjacent to the castle, with the spectacular structure providing a spectacular backdrop for the Brown Eyed Girl singer's headline performances.
Mr Campbell said Morrison has been keeping a keen-eye on the organising of the event.
"He wanted to do it and he hand-picks his shows," he said.
"What a fantastic backdrop for the event and what a great opportunity to showcase the glorious Causeway Coastal Route. It's going to be an historic two days."
In January, representatives of Exile Productions visited the castle to check its suitability and were delighted by what they saw. They held talks with Coleraine Borough Council and the castle's owners about the staging of the show.
The Belfast Telegraph first revealed plans for the concerts in February.
Together in harmony
• Music legends Van Morrison and Cliff Richard teamed up in 1989 to perform the track Whenever God Shines His Light.
• It was written by Morrison and released on his 1989 album Avalon Sunset as a duet with Richard.
• Morrison and Richard performed the duet on Top of the Pops in 1989 (right).
• The single charted at number 20 in the UK charts.