Bill Gates is barely noticeable during a sightseeing walk in Sydney

Bill Gates kept a low profile as he enjoyed a day outside the Sydney Opera House.

The billionaire was joined by a mysterious brunette as the couple strolled past the monument.

They visited the opera house on Monday and, according to a viewer, went largely unnoticed through the visit.

Mr. Gates, 67, the co-founder of Microsoft, ranked fourth on Forbes’ rich list last year.

He wore a casual baseball cap, blue polo shirt and Sydney sneakers.

Security teams were nowhere to be seen unless hidden in plain sight.

The bystander who saw Mr. Gates later said: “Nobody else noticed who Bill was or approached him. He was clearly trying to keep a low profile.

“No one could have imagined that one of the richest and most powerful men in the world was close by.”

Gates is in Australia on business and met with the country’s prime minister earlier this week.

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