The pastime has also benefited from a healthy dose of positive PR, with celebrities such as Rod Stewart publicly showing off his beloved model network. It was so expansive that it required seven shipping containers to relocate it to Essex from California.

An explosion in crafting and hobby television programmes, including shows like The Great Model Railway Challenge, first shown in 2018, and Hornby: A Model World – a “behind the scenes” look at the model producer, which aired in October – has also helped to draw in new aficionados, said Mark Holder, of auction house Hansons, who also owns his own model train shop.

“Stores like ours were forced to close our doors during the pandemic, but the business we lost was more than made up for by customers online – people stuck at home with time on their hands and often money still coming in from furlough pay,” he said.

“It can be a smart investment, especially if you are able to get your hands on a limited-edition model. These can almost double in value within 12 months of the particular model going out of production.”

Such collectors’ items often come with gold-plated embellishments and tack, as well as certificates which list the model’s issue number and prove their authenticity.

Mr Marsh said his investment strategy was to target limited-edition models of famous trains that are today housed in the National Railway Museum.

One of his most prized models is a limited production of the Mallard, which still holds the world record for the fastest steam train, clocking 126 miles per hour on the East Coast main line near Grantham in 1938.

“The main thing is the enjoyment of having them and building up more and more, but I will keep the most precious ones in their boxes in dry storage, and aim to keep them until my retirement to unlock a bit of money,” he said.

In some cases the true value of railway sets gathering dust in garages and attics across the country will be far higher than many people realise, Mr Holder added. “Unless you are in the know, it can be extremely difficult to assess the value,” he said.