Here's a movie about the almost invisible installation by Japanese architect Junya Ishigami that's on show at the Barbican art gallery in London.
Called Architecture as Air, the structure comprises a single curved line of columns that are only 0.9mm thick, seemingly floating unsupported in space. Closer inspection reveals a fine network of near-invisible supporting wires.
The installation is an extension of Ishigami's installation at the Venice Architecture Biennale 2010, for which he was awarded the Golden Lion for best project. It remains in place until 16 October.