In a bewildering but brilliant few hours, starting and finishing at the glorious Pont Alexandre III, as athletes of various categories chased each other through the river, on the bike and on the road, Great Britain’s triathletes finished with another heady haul – gold for Dave Ellis and Megan Richter, as well as a silver and two bronze medals.

Ellis, whose chances had been derailed mid-race in Tokyo by a dodgy chain on his tandem, won the men’s PTV1, with his guide Luke Pollard, more than a minute faster than the French duo of Thibaut Rigaudeau and Antoine Perel, who battled for silver, roared on by thousands of Parisians.

“After one lap [of the bike] I was like: ‘We’ve made it further than last time,’” Ellis said. “I’m tired, happy, that one was a long time coming.”

It was third time lucky for Ellis, who competed as a swimmer at Beijing, finishing sixth, before the Tokyo calamity. He had been a strong favourite in Paris, after a winning run in other competitions, but had to overcome various trials, including tripping over an extendable dog lead while out on a run and breaking both his arms early in 2022.

It was left to Claire Cashmore, who followed him into the Seine, winning silver in the PTS5, to fill in the gaps about her boyfriend, who she described as “a man of few words”.

“All I was bothered about as I crossed the finishing line was: ‘Please tell me Dave won.’ He’s the most determined, hard-working person I’ve ever met. I felt so stressed not being able to watch him, I’m absolutely buzzing.”

Cashmore’s silver was her 10th Paralympic medal at her sixth Games. “To cross that finishing line in silver was such a relief,” she said. “The crowd was just incredible, I think I just smiled the whole way.”

And she is hungry for more, with an eye on the Los Angeles Games in 2028, especially if a triathlon relay is included: “That would be huge inspiration. I love relays, love to be part of a team.”

There was a bronze in the same race for Lauren Steadman, the Paralympic champion from Tokyo. She wasn’t so sure about her sporting future after a tough 18 months. “I love my gold medal from Tokyo but it took everything I had in the last few years to get back on that start line today,” she said. “That bronze is just as special to me.”

Britain’s second gold went to the 23-year-old Megan Richter in the PTS4 (where Hannah Moore also won a bronze), fresh from studying for a masters and with dreams of becoming a scientist now on hold. “I’m in complete shock,” she said, “I’m so happy that my dream came true,” even if some of her friends and family had to go home without watching her, after the event was twice postponed over worries about water quality.

But in the end the Seine duly sparkled – as it was paid to do. The government spent €1.4bn on cleaning up the river – including building a super-sewer south of Paris and digging a huge basin under the Gare d’Austerlitz to catch 50,000m³ of filthy storm overflow which would otherwise have flowed straight into the Seine. By next year Parisians, too, should be able to swim in the river.

The British athletes had no complaint, Cashmore said. “It was amazing in there – clear, clean and just a really fun dynamic and so different to any other racing we’ve ever done, I don’t think we’ll ever get as iconic a race as that.

“I quite enjoyed the fact that it was a little bit challenging, we had the current, a little bit of controversy over that, we got the pebbles, which were a little bit technical – it just goes to show that on a world stage, with a variety of disabilities, everyone rose to the challenge.”

The swimmers set off from a floating pontoon just underneath the Pont Alexandre III, heading under the Pont des Invalides for a 750m swim, followed by 20km on the bike and a 5km run in front of Paris’s most outrageously beautiful monuments, including the Grand Palais. There the Tricolore flew proudly, as if to say admiringly “just look at this” – and it was hard to disagree.