Ford already has revealed its intent to occupy The Factory at Corktown on Michigan Avenue and put 220 autonomous/electric vehicle workers in the 45,000-square-foot building. But close to 50 properties, including the train station and small vacant lots, have been linked to Ford in the five weeks since Crain's first reported the company's discussions with the Moroun family.

"We are excited about our return to Detroit this year with our electric vehicle and autonomous vehicle teams relocating to the Factory in Corktown," Dawn Booker, a spokeswoman for Ford Land Development Corp., the real estate arm for Ford Motor Co., said in a statement.

"While we anticipate our presence over time will grow as our AV/EV teams move downtown, we have nothing further to announce at this time."

The result of the property assembly would be a large campus spread across at least 1.1 million square feet of building space sitting on at least 21 acres.

Almost all the properties are in the area generally bounded by Vernor Highway, 14th Street, the I-75 service drive, Trumbull Avenue, Rosa Parks Boulevard and Bagley Avenue.

Among them: The Detroit Athletic Co. building on Michigan Avenue, the Moroun-owned former Detroit Public Schools book depository and The Alchemy building on Rosa Parks Boulevard. A series of dozens of vacant parcels immediately north of the Bobcat Bonnie's restaurant on Michigan Avenue totaling almost 5 acres are also in play.

Multiple messages have been left with some of the owners over the last several weeks.

The train station discussions have continued for months. For the past several weeks, Crain's reporters have seen workers at the building with scaffolding and a construction platform erected on its western side. A spokesman for the Moroun family said last month that the crews were doing inspections but declined to provide any additional details about the nature of the inspections. The equipment has since been removed.

It's not known how, if at all, the Corktown campus would impact Ford's effort to transform its Dearborn headquarters in what two years ago was a planned $1 billion, 10-year effort to consolidate employees and renovate many of its buildings there. If Ford's plan comes to fruition, the total capital expense could near or surpass that amount; local and state tax incentives would likely be involved.

The company also is in the process of re-evaluating its Dearborn campus transformation plan.

Detroit-based SmithGroupJJR had completed its work on a master plan for the project, but when CEO Jim Hackett replaced Mark Fields, a team consisting of Oslo-based Snohetta Architects and Detroit-based Gensler was brought in to re-evaluate the plan, according to two sources familiar with the matter who requested anonymity.

Requests for comment were sent to the Moroun family, which built its empire in the trucking industry. CBRE Inc., which represents Ford on much of its real estate dealings, declined comment.

Editor's note: The original version of this report incorrectly identified the headquarters of Gensler. This version is correct.