Spectra

An unmissable part of the national commemorations of the Word War I centenary, this beam will pierce the sky over London from dusk until dawn for seven days this August. Japanese artist Ryoji Ikeda's bright column shines from Victoria Tower Gardens, where visitors can walk through its 49 static searchlights to experience an accompanying sound installation. The light, unsurprisingly, can also be admired from all over London: just look up.