Invisible 5 invisible-5 is an art project created by Amy Balkin, Kim Stringfellow and Tim Halbur which uses the methods employed by a self-guided art gallery tour to provide a self-guided tour of the portion of Interstate 5 between San Francisco and Los Angeles. It was initially distributed on two compact discs, but is now available for download. It has been featured in Metropolis Magazine and the Southern Exposure gallery.