Former Happy Days co-stars Ron Howard and Henry Winkler have reunited in Sydney, 40 years after the hit sitcom that made their names.

Winkler, who played The Fonz in TV’s Happy Days, posted a photo with Howard (who played Richie Cunningham) to X on Wednesday.

“As the world turns, Ron Howard⁩ came to my book event in Sydney Australia. So exciting for everyone,” he wrote.

Winkler, 78, is in Australia to promote his memoir Being Henry: The Fonz … and Beyond.

Oscar-winning filmmaker Howard, 69, has been in Australia filming Eden, with Sydney Sweeney.

The survival thriller, which is mostly filmed on the Gold Coast, is reportedly based on a true story “set around a group of eclectic characters who abandon civilisation” for a remote island in the Galapagos. Along side rising-star Sweeney (Euphoria, The White Lotus), Eden‘s A-list cast includes Ana de Armas (Blonde) and Jude Law (The Talented Mr Ripley, Sherlock Holmes).

“Just started post-production in Sydney on my recently wrapped latest movie Eden, starring an amazing cast,” Howard wrote as he shared Winkler’s X post.

Tweet from @hwinkler4real

“A great creative experience but that’s for another post. When I touched base with Henry, I discovered he was making an appearance here in support of his excellent best-selling memoir Being Henry: The Fonz … and Beyond. Fantastic!

“We connected backstage and I watched him give a great speech to a huge crowd. What a blast!”

Happy Days ran for 11 seasons from 1974 to 1984. Set in suburban Wisconsin in the 1950s and 1960s, it followed the Cunningham family, including son Richie (Howard) and daughter Joanie (Erin Moran), as well as Richie’s friends Potsie (Anson Williams) and Ralph (Don Most) – and  local bad boy, Arthur “Fonzie” Fonzarelli (Winkler).

Winkler has spoken previously of his fond memories of the show, and his long-lasting friendship with Howard.

“Ron, he’s an old soul. There’s a wisdom in him that is big,” he told Today back in November.

He also shared how how Howard stepped in when Winkler – who is dyslexic – lost his temper and punched a script after struggling with his lines in the show’s early days.

“Now Ron Howard was almost 10 years younger than I was. But Ron had been around the block a lot more times than me,” he added in his memoir.

Howard put his arm around Winkler and took him outside to explain that he shouldn’t punch a script.

“The writers are working as hard as they can,” Winkler said Howard telling him. “They’re trying really hard.”

“I went, ‘Ron, I’ll never do that again … And that was the beginning of our friendship.”