One of them is the Kemper Building Observatory. In 1962, the Kemper Building opened with a restaurant on the 41st floor, showing off the city's skyline. Today, that same space is basically empty. But on Saturday and Sunday, October 13 and 14, it will open as an observatory for the public as part of the Chicago Architecture Foundation's 'Open House Chicago.'
"At the time in 1962 when it was opened, it was the tallest marble-clad building in the world -- complete with modern amenities, like air conditioning," Diana Hickert-Hill, Kemper spokesperson, said. "We're going to bring people right up here to 41 and let them wander around completely the perimeter of the building and look at all the windows. It's a 360-degree view of the city."
'Open House Chicago' is in its second year.
"There are going to be 150 sites and they go all the way from Rogers Park down to Hyde Park and out to Garfield Park," Lynn Osmond, president, Chicago Architecture Foundation, said.
For more information on how to take part, visit www.openhousechicago.org.