Bilbao doesn’t fit the usual tourist images of Spain: flamenco dancers, hilltop castles, Moorish palaces. In fact, until 20 years ago, this gritty industrial port on Spain’s north coast was hardly known to tourists at all.

Now more than a million visit each year, and the city’s name is synonymous with the travel trend it created — architourism. As if that were not enough, the city also gave its name to an economic phenomenon known as the Bilbao Effect.

How did Bilbao transform itself from an ugly, run-down industrial wasteland to a glittering city where tourists come just to stand and marvel at its buildings and bridges? It’s a story of foresight and vision, and one that elevates risk-taking to a fine art.

The ambitious redevelopment program began in the late 1980s with a new airport and a stunning footbridge, both designed by acclaimed architect Santiago Calatrava. Then a performance and convention center, the Palacio Euskalduna, was erected on the riverside site of the former shipyard. Following discussions with the Guggenheim Foundation, work started in 1993 on Frank O. Gehry’s design for a building that would knock the socks off the architectural world. The reaction to the opening of Guggenheim Museum Bilbao in 1997 surpassed the city’s wildest dreams; within only three years, revenue generated by Gehry’s masterpiece more than exceeded its cost.