The boat – which Ms Rinehart said was at its capacity of 120 people (some had missed out) – featured some of Australia’s best-performing Olympians as well as key stakeholders from swimming, rowing, athletics and beach volleyball.

“It’s wonderful to be with you,” Ms Rinehart said as they prepared to embark. “It’s 100 years from the last Paris Olympics, so we’ve decorated the boat inside with photos from the last 100 years of the Olympics. I hope you enjoy those and a few other little mementos as we go along.”

The party was originally intended for the rowers and swimmers who receive millions of dollars in funding from Ms Rinehart each year, but was extended to include other medallists in windsurfer Grae Morris, cyclist Grace Brown and equestrian rider Chris Burton.

The trio were joined by rowers Jessica Morrison and Annabelle McIntyre and swimmers including Ariarne Titmus, Elijah Winnington, Kyle Chalmers, Lani Pallister and Mollie O’Callaghan, who took the opportunity for selfies in the sun underneath the Eiffel Tower.

There were some notable absentees too – decorated Olympic swimmers Emma McKeon, Kaylee McKeown and Cameron McEvoy among them.

Among those boarding with the medallists were Australia’s ambassador to Paris, Gillian Bird; Matt Carroll and Ian Chesterman from the Australian Olympic Committee; Wesfarmers boss Rob Scott; Rowing Australia chief executive Sarah Cook; the feted swimming coach of O’Callaghan and Titmus, Dean Boxall; rental property owner-operator and Volleyball Australia president Craig Carracher; and Peter Bromley, head of Athletics Australia.

The party took off on the riverboat on Monday afternoon (Tuesday morning, AEST), travelling down Paris’ famous river to take in city landmarks such as the Eiffel Tower, Notre Dame and the Louvre.

The Ducasse Sur Seine is touted as a luxury dinner cruise ship with a menu curated by legendary Michelin-starred Parisian chef Alain Ducasse.

It was a fitting way to cap off a historic start for the Australian Olympic team, which won a gold medal every day of the first week of the global tournament. Australia’s rowing team delivered its worst performance since Seoul in 1988, but the swim team managed to collect a total of 18 medals – including seven gold.

In an interview on Monday, silver medallist Winnington said the money from Ms Rinehart ensured the athletes could afford to swim as a career.

“She also is almost like this godmother figure,” he said. “I don’t know many other financial backers would come to the swimming every single night, waving the Australian flag and standing up for every single person’s race.

“Without her financial support, we would have nothing other than prize money.”

As he went onto the boat, Boxall said he hoped his athletes celebrated their success. “Have the best time you possibly can. There’s no river in Los Angeles,” he said, referring to the 2028 location of the Games.

That may be so, but there is always Beverly Hills.