Exit sign at the Lincoln Park Zoo. Chicago code requires that exit signs be made of steel, and that the face is a backlit glass panel with "EXIT" written on it in red. Any arrows must be beneath the lettering rather than beside it.
Ben Schumin is a professional photographer who captures the intricacies of daily life. This image may be used under Creative Commons Attribution-ShareAlike 2.0. Please provide artist attribution, as well as a link to the original photo and to the license terms.