Bilbao Fine Arts Museum

Now, a dramatic new addition named the Agravitas hovers like a bridge, spanning 55 metres over the original buildings, leaving them untouched except for restoration.

For the first time in many decades, the original 1940s entrance fronting the city square is reopened. The uppermost level houses a vast new column-free gallery.

The flexible new building looks ahead to the future and responds to the ever-changing form of contemporary art, while remaining respectful of the site's storied history.

The international competition jury unanimously chose the design and summarised the strengths of the project as follows: "Technological in its image, humanistic in its approach and ecological in its sustainability, the latest extension to the proposal combines architectural quality, urban sensitivity and social responsibility to raise a luminous and light landmark in the historic heart of Bilbao."

Rationalising the circulation between the new and old buildings has reinstated Plaza Arriaga as a pure volume, thus creating a clear public focus for art and events. Its design is centred on Francisco Durrio's sculptural fountain, dedicated to the celebrated Bilbao-born composer Juan Crisóstomo de Arriaga. The new daylight-filled atrium features sculptures by Richard Serra, Pablo Palazuelo, and Eduardo Chillida.

Agravitas increases the area of the original buildings by 60 percent and introduces 2,300 square metres of flexible exhibition area on two levels to accommodate a wide range of exhibits alongside facilities for educational programmes, workshops, and office spaces.

The new building is an expression of the city's industrial heritage featuring steel that has been produced locally.

At the upper level, it creates a vast new column-free gallery of 1,300 square metres, with natural light filtering through skylights that can be tuned for the widest range of exhibitions – from full daylight to complete black out.

The reopening of the museum has also been heralded by gifts from three generous donors – the Arango family and Patricia Phelps de Cisneros have both made significant contributions to the museum, lending important works from their collections for display and donating key pieces to its permanent holdings, while Norman and Elena Foster have presented Book Stack (2007) by Anselm Kiefer, and two sculptures by Anthony Caro – Toronto Flats (1974) and Low Line Flats (1974) – to the museum on permanent loan.

The photovoltaic panels generate enough energy to cover 50 percent of the museum's thermal demand. The existing buildings have been upgraded to meet modern standards, significantly increasing their lifespans and combining the best of old and new into one unified sequence of museum spaces.

The team comprises structural engineers, MC2; environmental engineers, Valladares Ingenieria; façade consultants, Enar; contractors are a joint venture of four Basque companies – Urbelan, Altuna y Uria, Campezo and Teusa; and façade contractor, Martifer.