Outdoor media firm says cryptic tube campaign demonstrates how interactive outdoor advertising can be.

The outdoor media company has been secretly running the posters for several days as a teaser to a city-wide challenge that has been generating considerable interest on Twitter through the hashtag #lookforlonger.

CBS Outdoor says the aim is to highlight how interactive advertising on the underground can be when people are using Wi-Fi while waiting for their trains. The company runs several campaigns each year to showcase to advertisers how engaged consumers can be with outdoor advertising.

The ‘Look for Longer’ campaign launches officially today (3 October) and asks participants to solve the visual clues featured on a poster to name 75 tube stations across the London Underground network. The campaign runs for four weeks and spans Twitter and Virgin Media’s Wi-Fi tube network as well as traditional outdoor formats. Answers can be submitted via a campaign site and will be entered into a prize draw.

Simon Harrington, marketing director at CBS Outdoor UK says: ‘We wanted to create a campaign that would generate curiosity, intrigue, and interaction. The three minute dwell time on platforms, coupled with Wi-Fi connectivity not only provides the perfect environment for advertisers to reach a highly responsive audience, but it also offers extended engagement – that is to say the audience do something as a result of seeing it, be that playing the game, or sharing it with friends through social media. All our research shows that meaningful interaction leads to positive brand affinity.”