London and Barcelona now have maps of how they smell.

Ever navigated by following your nose? A number of brave researchers are  sniffing their way around several global cities in order to create a series of "city smell maps." I'd love to see one for sound, and for viewshed (line of sight) analysis. There are many, many ways to experience places we know.

(See also: Alexandra Horowitz's "On Looking": http://www.brainpickings.org/2013/08/12/on-looking-eleven-walks-with-expert-eyes/)