Edinburgh Airport, Scotland, United Kingdom (EDI/EGPH)
Originally a military airport, Edinburgh Airport opened to commercial aviation in 1977. It is now Scotland's second largest airport after Glasgow. Edinburgh's new control tower took 15 months to complete and opened in 2005. It stands 57 meters (187 feet) high, which equals 12 double-decker buses stacked on top of one another. The exterior's crisscrossed, double-helix pattern is not just for aesthetics. It also functions as a system of drainage channels. The 9,216 zinc tiles were hand-installed and have aged naturally in the outside environment, reducing the need for maintenance.
The photograph is a part of Art of the Airport Tower, an exhibition that explores contemporary and historical air traffic control towers in the U.S. and around the world.