And over the past quarter century, the Guggenheim has become an important center for modern art, with works by artists from the region (Basque Country) and international giants such as Andy Warhol, Jackson Pollock, and Alberto Giacometti.

But perhaps the museum’s greatest legacy is the broader impact it has had on the northern Spanish city, a phenomenon known as “The Guggenheim Effect”.

In the 1900s, low-phosphorus Bilbao, extracted from the nearby hills and transported along the River Nervión, turned Bilbao into an industrial powerhouse.

At the end of the 19th century, the city supplied Britain with two-thirds of its iron ore and in the following decades provided a fifth of the world’s steel.

But by the end of the 20th century, decline had set in and Bilbao’s image was that of one polluted industrial wastelandwhile the city and the surrounding region had become frequent targets of the attacks by the Basque separatist group ETA.

Basque writer Jon Juaristi described it as “the least hospitable city in all of Spain”.

Thomas Krens was a director of the Solomon R. Guggenheim Foundation in New York, which wanted to expand abroad. When a project discussed in Venice failed, the plan for a new museum in Bilbao was born.

“The Basques came to me and asked how they could change the misconception that they were only famous for terrorism and Jai alai handball,” explains Paddy Woodworth to the author, referring to this sport of Basque origin, also known as cesta punta or vasca ball. “I told them to build the greatest building of the century.”

The Canadian architect Frank Gehry he was commissioned to design it, in a spot on the river bank.

From the start, the Guggenheim Bilbao project was criticized largely for cost (US$100 million just for the building) paid by the local authorities.

For the Guggenheim Foundation, which merely lent its name and artwork, the risk was significantly reduced.

But the gamble paid off.

“Physically, it literally cleaned up the city. That’s what happened when they opened this museum,” said Lekha Hileman Waitoller, an American-born curator at the Guggenheim Bilbao.

“It made residents, the government and everyone in control of these decisions look to the river.”

The new ultra-modernist structure attracted a large number of tourists.

The new revenue spurred a regeneration of the city’s waterfront, and new bars, cafes and other businesses sprang up, many of them high-tech.

There are currently six Michelin star restaurants in a city of just 350,000 people.

“In a very, very short time, it really changed the whole face of Bilbao,” says Hileman Waitoller of the museum.

Some believe the museum’s gaudy design undermines its role as a house of art.

Critic Hal Foster said Gehry had “given his clients too much of what they wanted, a sublime space that overwhelms the viewer.”

“The building is an incredible event and it’s what I’ve always wanted to see,” says Eve Vanvas, who visits from the UK, as she exits the museum. “There’s a lot of interesting art on it, but really we came to see the building“.

With 25 million people having visited the museum since it opened in 1997, Bilbao’s local government and its citizens don’t seem to complain, even if it’s the building, rather than the art, that draws them in.

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