Planning began in 1959. The first drawings of the project included two 40-story rectangular buildings, but the “footprint,” or required surface space, would have overwhelmed the site. Goldberg submitted a second design in which the towers were 65 stories and round.

Wind tunnel tests at Illinois Institute of Technology concluded the new shape was more efficient, at least more wind-resistant.

The idea of round buildings may have come from an earlier, rejected design for Executive House (now Hotel 71), a hotel built in the north Loop in 1960. Or it may have come from Chinese-American architect I. M. Pei, who in 1949 designed “The Helix,” a 22-story cylindrical apartment building for New York developer William Zeckendorf.

Geoffrey Goldberg, the architect’s son and himself an architect, has his own theory. In 1952, his father completed work on a design for a railroad car. Because of a steel shortage, the challenge was to design a rail car that used steel more efficiently. According to Geoffrey’s own research into his father’s work, Goldberg created a “monolithic tube-like structure” made of layers of strong plywood. The plywood was then laminated under heat with special plastics.

The “Unicel Prefab Freight Car” was unveiled with much fanfare at Merchandise Mart in Chicago and The Waldorf-Astoria hotel in New York. (Left) Exterior of a Unicel freight car. Inside was a tube constructed of specially-laminated plywood.

“I believe the boxcar done in the early 1950s was for my father the real structural breakthrough. It is a tube structure. And put that together with the use of curved concrete in a later project – work in the mid-50s for a sewage plant in Nashville – and it’s not too far to get to a vertical tube, the concrete core, at the heart of the towers at Marina City.”

Inside the core were elevators and stairways, surrounded by a circular corridor, then a ring of bathrooms and kitchens, followed by living quarters and balconies. The Helix was never built. A version of it was proposed in the mid-1950s for lower Manhattan, but that wasn’t built, either.

Goldberg did design a cylindrical motel in 1957 that was never built. The idea may have endured and found its way into the design of Marina City two years later.

The unusual shape wasn’t the only problem. The Federal Housing Administration initially turned down the loan request because, according to Goldberg, single adults or couples living downtown did not meet their standard of a “family.” Goldberg went to Washington, D.C., personally – more than once – to lobby for Marina City and get the FHA to broaden its interpretation. Furthermore, the mixed use (commercial and residential) violated zoning regulations. Goldberg worked with Planning Commissioner Ira Bach, who supported the project and got the necessary approvals.