Barcelona’s famously cucumber-shaped tower, Jean Nouvel’s luminous 38-storey Torre Glòries is among the most daring additions to the skyline since the first towers of La Sagrada Família went up. The building's top floors have been transformed into a viewing platform, with an installation by Argentinian artist Tomás Saraceno set into its dome; the lift zips up 30 floors in 34 seconds.
