The first question that must be asked is, why not in Yorkshire?

Dr Jeffrey Sherwin, honorary alderman of Leeds and former chairman of Leeds Leisure Services, is the proud owner of one of the most significant collections of British surrealist art.

That collection, usually kept at his home, is now on display at the new £14.2m Middlesbrough Institute of Modern Art (Mima).

Again, why not Yorkshire?

Dr Sherwin bristles at the question and his terse reply is: "I've never been asked, it's as simple as that."

Simple as that?

"I'm only too happy to loan the collection to Leeds City Art Gallery, you'll have to ask them why they haven't taken it."

But this is not to be a war of words between one of Leeds's foremost art collectors and the city's leaders, this is a celebration of the beneficence of a former GP whose love of surrealism he is happy to be sharing with the world.

More than 200 pieces make up a collection built by the good doctor in slightly more than two decades. He started collecting in 1986 after visiting a tribute exhibition held in Leeds to a surrealist exhibition held at London's New Burlington gallery in the Thirties.

"It created such a furore – the crowds queuing for the exhibition literally stopped the traffic in Piccadilly Circus," says Dr Sherwin.

It had an equal impact on the doctor. With his interest aroused, he decided he would buy his first piece of art.

Merlyn Evans's The Chess Players – which shows Molotov and Ribbentrop playing chess for Europe to illustrate the 1939 Russo-German non-aggression pact – was bought for £1,250.

His appetite grew. He bought another piece and another. Soon the collection rivalled anything in private collections, then anything in some gallery collections, to the point where it became one of the most significant collections in the country.

"My wife is pleased to be able to finally decorate the walls," says Dr Sherwin from his Middlesbrough hotel room, where he spent the days before the opening watching the final touches being put to the exhibition.

The exhibition came about as simply as the reason it hasn't yet happened in Leeds.

Dr Sherwin was visiting Mima and was talking to the director, Godfrey Worsdale.

"He asked if we could display the collection and I said yes," says Dr Sherwin.

Worsdale visited the home of Dr Sherwin and was amazed at the collection.

"The breadth of his investigation is apparent as you make your way through his home in Leeds," he says.

"For Jeffrey and his wife Ruth, collecting has become a consuming passion and a life's work. The results are a radical, anarchic gesture, in many instances at odds with conventional history.

"In the dining room, a 1925 frottage by Max Ernst, a 1947 collage by Kurt Schwitters, a 1951 bronze sculpture sit cheek by jowl."

This collection is given space to breathe in Mima.

Dr Sherwin says: "I think of myself as a custodian rather than an owner of these pieces.

"It has been fascinating watching a curator bring the pieces together and arrange them in a purpose-built gallery."

Dr Sherwin's drive becomes clear when he talks about the field of art which most appeals to him – British surrealism since the Fifties.

"Surrealist art contains three main elements," he says.

"First, it's fun. Second it is full of ideas. Ideas that one would never have had oneself except in one's dreams. And third, surrealist art should always contain an element of surprise.

"British surrealist art has been neglected by the art establishment, but there is excellent work from the Fifties, right up until the modern day in my collection."

And now, even if they have to travel north to see them, the public of Yorkshire will get to share in the collection too.

British Surrealism and Other Realities: The Sherwin Collection is now on display at Mima until August 17.