The 22 most out-of-the-box outdoor ads this year

It may be one of the oldest forms of advertising in the world, but marketers are becoming increasingly creative with their outdoor campaigns.

No longer just confined to static billboards, global brands this year have been conjuring up some truly creative interactive ads that are actually a joy to look at and play with.

We've picked out some of the best so far. Expect to see them pop up again as we head into award season.