Northern Line Extension Will Light Up With 'Bat-Signal' Beams | Londonist

Northern Line Extension Will Light Up With 'Bat-Signal' Beams | Londonist: 

... Line of Light — happening on the evenings of 29 and 30 October — follows the two-mile London Underground line between Kennington and Battersea Power Station, shooting Bat-Signal-esque beams up into the night skies. ...