And you thought painting the Golden Gate Bridge was a rough job.
A series of dizzying photos show what it's like to clean and polish the underside of the Grand Canyon Skywalk.
Nerves of steel and a hatred of dirt are definitely prerequisites when it comes to dangling 4,000 feet above the Colorado River so tourists can have a nicer view.
Yahoo News spoke with Kenneth Piposar, vice president at Abseilon USA, the company responsible for cleaning the walkway.
He said the walkway is cleaned quarterly, and it takes the six technicians one day to do the rigging and another day to clean the glass. He described their safety record as "impeccable" and explained that the technicians have at least 200 percent fall protection at any time, meaning they are attached to multiple anchors while cleaning.
"These guys have thousands of logged hours on ropes," he said.
The walkway juts out over the Grand Canyon. Viewers brave enough to look down are treated to an amazing view of the Colorado River, made all the more crisp by the work of these technicians.
Follow Mike Krumboltz on Twitter (@mikekrumboltz).
- Grand Canyon Skywalk