Rod Stewart performs for thousands hours after shocking small Western Sydney shop owners with surprise visit

By night, he's among the best-selling music artists of all time. But by day, he's your average model train enthusiast.

Hall of Famer Rod Stewart, 78, stepped onto the stage at Sydney's Qudos Bank Arena on Wednesday night, performing his classic hits in a leopard print jacket and black-and-white pinstriped trousers.

He may have spent the evening wowing a crowd of thousands, however, hours earlier, the Maggie May singer's life could not have looked more different.

Watch the video above.

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Stewart shocked staff at Woodpecker Model Railways, a model train store located in Pendle Hill, with a low-key visit before his Wednesday concert in search of model trains to add to his vast collection.

"Look who casually walked into our shop," the business shared on their Facebook page, alongside a photo of staff members smiling with the rock legend.

"That's amazing!!!" one follower wrote on Facebook.

"WOW how awesome !! Lucky you !!I think I would be in total admiration [and] shock if Rod walked into a shop I owned or was in lol," another said.

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"A very accomplished modeller..... sings a bit as well....." another wrote.

Stewart indeed is a keen model train builder, revealing in a 2019 interview with Railway Modeller magazine that he had been working on a giant and intricate model of a United States city at home for the previous 23 years.

Following the interview, BBC Radio 2's Jeremy Vine suggested Stewart did not build his model himself, to which Stewart rebutted by calling into Vine's show to set the record straight himself.

"I would say 90 per cent of it I built myself," Stewart insisted to Vine. "The only thing I wasn't very good at and still am not is the electricals, so I had someone else do that."

"A lot of people laugh at it being a silly hobby, but it's a wonderful hobby," he said.

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In the time it took to build the city, which is based off New York City and Chicago around 1945, Stewart had also toured 19 times and released 13 studio albums.

He takes the hobby with him around the world, revealing to Railway Modeller he often requests extra hotel rooms for his mini construction sites.

Stewart has been on a highly-publicised tour in Australia in recent weeks with Cyndi Lauper and Jon Stevens, and notably, he was forced to cancel his Geelong, Victoria tour at the eleventh hour "due to illness".

Days later, he assured his fans in Adelaide the show would go ahead after Victoria's "slight setback", with Geelong's replacement show scheduled for Friday, March 31.