If you are one of those who doesn't get enough sleep, then you might want to avoid these creepy vintage photos. They'll fuel your nightmares, and they certainly won't help you in the sleep department...
At the end of the track in Glacier Point, Yosemite National Park.
New York construction workers.
Working like acrobats at high altitudes, Woolworth Building, New York, 1926.
New York construction workers at insane heights.
Construction workers eat lunch atop a steel beam 800 feet above ground, at the building site of the RCA Building in Rockefeller Center in New York, on Sept. 29, 1932. Also, check out the previously unpublished version of the iconic photograph.
A construction worker in New York City, 1930s. Not a lot changed over the decades.
The Empire State Building. Five men died during its construction, from 1929-1931.
Photographer Margaret Bourke-White on the Chrysler Building, 1935.
Auckland Harbour Bridge workers.