I can think of a couple twin towers at The Ohio State University when I was there (known facetiously by students and parents as Sodom & Gamorrah in the age of free love). The massive concrete staircases are exposed throughout the exterior of the building at Unite d’Habitation Le Corbusie...
OHIO: Toledo, Sylvania, Maumee, Perrysburg, Oregon, Bowling Green, Findlay, Waterville, Rossford, Lima, Point Place, Wauseon, Oak Harbor, Fremont, Sandusky, Port Clinton, Genoa, Archbold, Fremont, Montpelier, Delta, Napoleon, Swanton, Huron, Whitehouse, Delta, Tiffin, Fostoria, Clyde, Bellevue...