An 18-foot replica of Donald Trump’s border wall has been scaled in a matter of seconds by novice climbers, an eight-year-old girl and a man who returned for another attempt while juggling with one hand.

The US president described his wall as “virtually impenetrable” during a trip to the US-Mexico border in September, claiming 20 “world class” mountain climbers had told him his chosen prototype was difficult to climb.

“We had 20 mountain climbers. That’s all they do, they love to climb mountains … some of them were champions,” Mr Trump said. “And we gave them different prototypes of walls, and this was the one that was hardest to climb … this wall can’t be climbed.”

His remarks were taken as a challenge by 75-year-old Rick Weber, co-founder of Muir Valley, a rock climbing park and nature reserve in Kentucky.

“You don’t tell a bona fide rock climber something’s impossible to climb,” he told Time magazine.

Trump prototypes for Mexico border wall demolished in California Show all 20 1 /20 Trump prototypes for Mexico border wall demolished in California Trump prototypes for Mexico border wall demolished in California The prototypes for President Trump’s border wall are being demolished. AP Trump prototypes for Mexico border wall demolished in California The US Customs and Border protection had built the eight 30-foot tall steel and concrete models near San Diego on the US-Mexico border. Reuters Trump prototypes for Mexico border wall demolished in California A 2018 report from the Government Accountability Office found that the construction challenges presented by the four concrete models would be “extensive” and those presented by two of the other models would be “substantial”. Reuters Trump prototypes for Mexico border wall demolished in California It was intended that Mr Trump would choose his favourite of the designs after testing had been completed. AFP/Getty Trump prototypes for Mexico border wall demolished in California The President is yet to comment. AFP/Getty Trump prototypes for Mexico border wall demolished in California Each prototype cost $300,000 to $500,000 to build and they are being knocked down in order to make way for the San Diego Secondary Wall project which will see up to 14 miles of barrier being built to support the existing steel border fence. AP Trump prototypes for Mexico border wall demolished in California The new barrier will not employ the design of any of the prototypes, instead being built of the favoured steel bollards which make up the current section of the wall at San Diego. Reuters Trump prototypes for Mexico border wall demolished in California The new secondary barrier being built near San Diego. Reuters Trump prototypes for Mexico border wall demolished in California The rubble of one of the demolished prototypes. Reuters Trump prototypes for Mexico border wall demolished in California A steel wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A wall prototype made from a mix of steel and concrete AFP/Getty Trump prototypes for Mexico border wall demolished in California A wall prototype made from a mix of steel and concrete AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A steel wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A concrete wall prototype AFP/Getty Trump prototypes for Mexico border wall demolished in California A digger approaches the prototype wall AFP/Getty Trump prototypes for Mexico border wall demolished in California Aerial view of the wall prototypes at the US-Mexico border after they were torn down AFP/Getty Trump prototypes for Mexico border wall demolished in California An aerial view showing Tijuana, Mexico on the left and the demolished wall prototypes on the right AFP/Getty

Mr Weber, a retired engineer, decided to build a replica of Mr Trump’s wall using official dimensions and recent images of the structure.

He wrote in to popular climbing magazine Rock & Ice to announce a climbing competition on 11 and 12 October to coincide with Rocktoberfest, one of the largest annual gatherings of climbers in the US.

“No one in our climbing community knows any of these 20 mountaineers. I doubt if they exist,” he wrote. “More importantly, to declare something to be impossible to climb to a bona fide rock climber is to issue a challenge.

“So, I decided to build an exact replica and hold a competition.”

Ahead of the official competition, several people had already managed to climb the wall.

Among these was eight-year-old Lucy Hancock, who climbed the replica using a belay – a rope that acts as a safety measure, rather than an aid. Footage showed her scaling the majority of the wall in little more than a minute.

Erik Kloeker, a 29-year-old climbing guide and property manager at Muir Valley who told The Courier Journal he had been climbing for nine years, climbed the structure in about 30 seconds in a demonstration.

“The border wall that they’re building could be climbed pretty easily,” said Mr Kloeker, who juggled several items in one hand during repeat attempts.

Mr Trump’s border wall is being built at heights of 18-feet and 30-feet, consisting of singular pillars and a larger panel along the top.

Mr Weber told Time that as the large top panel is the same size, a climber who manages to ascend pillars of the 18-foot version would have no difficulty scaling the additional distance.

He decided to allow climbers to hold on to the side of the top panel, as he claimed such gaps existed between each section of wall in the real designs.

The retired engineer said a wall without pillars would be far more difficult to climb.

“I’m not making an argument that we shouldn’t have a secure border. I’m not doing that at all,” he said. “What I’m trying to do is to make sure that we’re not blowing a lot of money on some silly nonsense of putting up something that he thinks can’t be climbed. Because it can. And will be.”

During his September visit to the San Diego border, Mr Trump claimed hopeful climbers would “have to bring hoses and waters [sic]” to combat the large top panel of the design, which he said was designed to absorb enough heat to “fry an egg”.

Mr Trump recently denied making enquiries about creating a moat filled with alligators and snakes along the border.