Unbeknown to Jane Batty, former pest control chief at Hull Council Adrian Batty had amassed a huge collection over 30 years, leaving a room so packed it was difficult to get more than a few steps inside.
But Mr Batty, who died last April, probably never ran a train around a loop of track, because although he had the boards, he never did a layout, she said.
Over 130 locomotives, thousands of items of rolling stock and an extraordinary range of rare trackside accessories are going under the hammer on Thursday at Scarborough auctioneers David Duggleby.
"I knew a bit but I didn't know how much he had collected. His sister was shocked by the volume as well. I think he did it when I wasn't in," said Mrs Batty.
"He had lots of boxes that were in plastic boxes, so you couldn't see what was in them and they lined the walls. It was one of those rooms where everything got dumped."
A catalogue - found by Mrs Batty and her relatives after going through box after box - revealed exactly where they had been bought, their condition and for how much.
She thinks he bought them to relive his childhood - and have a collection that his mother wouldn't let him have.
She said: "He had an amazing train set when he was a kid - his dad worked at British Aerospace as an engineer. He set it up so it had electric lights and it was really beautiful. Then his mum got cross as he left it out for too long and she sold it while he wasn't there - I don't think he ever forgave her."
Specialist Graham Paddison aid the collection, which spans the entire 25-year Hornby Dublo period, from its launch in 1938 through to the early 1960s, was “just one gem after another”.
He said: “It is an extraordinary story and it is by a country mile, the most extraordinary private collection we’ve ever seen.
“Mr. Batty was dedicated and knowledgeable. He hunted down the rarest items, in the finest condition, meticulously recording the details in his inventory – including whether he had bagged a bargain or paid over the odds.”
The collection includes no fewer than eight versions of the world steam record holder Mallard, five versions of Sir Nigel Gresley, six Silver Kings, two Golden Fleeces and a Golden Eagle.
There's also Castle Class, Duchess Class, West Country Class and even Canadian Railways locomotives, as well as Deltic and Diesel Electric models and fifty tank locomotives of various ages and types. Rarities include a Southern Railway 0-6-2 tank locomotive set in a malachite green colour, rather than the usual olive, with two wagons, a guards van, a quantity of track and a controller estimated at £350-£450.
The catalogue is available on the Internet (davidduggleby.com). Viewing at the Vine Street Salerooms in Scarborough is Wednesday 10am-6pm and Thursday from 9am until the start of the auction at 11am. The sale is to be webcast, with online bidding through DD Live and thesaleroom.com.