"Now I can ride alongside my wife when she goes for walks. It's my own personal mobility scooter. And it folds up small so I can take it on the train."
Does he get strange looks? "Ooh, yes," he says, laughing.
When he pauses after several laps around the fountain, a pot-bellied man steps forward looking incredulous.
"What is that?"
"A YikeBike."
"Yike?" he tries out the word as Mr Monro hoons off down the path.
But Mr Monro is used to strange looks and inquisitive strangers.
He owns a hovercraft and a hang-glider - which he's attached to the hovercraft - bloKarts and four YikeBikes, plus his own inventions.
The son of a mining engineer, Monro was born in Georgetown, Malaysia, and moved to New Zealand in 1968 from boarding school in the UK.
At the age of 11, in Machu Picchu, he was mesmerised by condor birds and subsequently became obsessed with flying.
"When I was courting my wife, I promised her a trip to South America. Thirty years later we made it. I went up into the Andes and managed to find the condors and went flying with them."
In the 1970s, he became a hang-glider test pilot and designer in Europe.
"I've always been interested in how things work and hang-gliding's my main passion," says Mr Monro, who once took off from Mt Wellington and cloud-hopped his way to Devonport.
"I was involved in testing and designing the Super Scorpion, one of the best hang-gliders of the 70s. That's where I developed my love of making and designing things."
Since then he's invented a raft of sky-bound machines. "I designed the SkyCat, a flying catamaran. You tow it behind a speedboat and the whole thing takes off and flies.''
His crash test dummy?
"The first passenger was Simba, the dog. Then my son.''
Next came the SkyBird, described as a long flying fox with a hang-glider attached.
The last time The Aucklander met Mr Monro was to see him launching a hang-glider from behind his hovercraft. His test pilot narrowly missed clipping a house beside Cheltenham Beach, and a complaint was made.
"Oh, it was just council calling to make sure I wasn't doing it as a commercial thing,'' says Mr Monro, shrugging.
Before the interview is through, he's made an attempt to recruit the photographer to ride a YikeBike while towing him in a hang-glider.
The photographer questions the likelihood of being lifted up into the sky, too.
"Oh we'll just strap some weights on to your legs.
"I enjoy people telling me I can't do things, that it's impossible. There are always things in the pipe
line,'' says Mr Monro of his never-ending visions. "I want to put wings on the hovercraft. When I was [young] I had so many ideas. But it's a case of time and money. Patents are so expensive. There are millions of inventions out there
and 99.9 per cent of them go nowhere - while patent lawyers are creaming it.''
Mr Monro teaches hang-gliding and recently attended the Birdman competition in London to support one of his students attempting to fly 100m off a jetty.
When not passing on his passion to other people, he runs Aqua Air Adventure taking groups out to have a go on a YikeBike, hovercraft or bloKart, and he also visits schools.
"I talk to them about the origins of flight and about inventions like the hovercraft. I'd like to see more kids encouraged into creativity, in the areas of engineering, physics and science."
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To find out about Aqua Air Adventures see: www.gethigh.co.nz
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