Earlier this month, it emerged that Dan Gilbert has a formal option to buy the main portion of the Renaissance Center from General Motors Co.

Obviously, that would be a major shakeup in the downtown commercial property market as the billionaire mortgage and real estate mogul continues his decade-plus shopping spree for Detroit buildings and land.

But don’t overlook the other key component of the option agreement: Approximately 20 acres of east Detroit riverfront land next to the RenCen that Gilbert has long coveted.

It’s been a long road for the site, grand visions for which go back to the time the Renaissance Center was announced in 1971. 

The land, owned by GM primarily for surface parking, is one of the most underutilized properties downtown, a nagging reminder that the Detroit riverfront, in spite of the major glow-up and accolades it has received the past 20 or so years, still has a long way to go as new development remains elusive, save for a new apartment or condo building here and there. 

Gilbert, for his part, has for close to two decades seen that plot with an eye toward building on it, following in the footsteps of others before him who tried and failed.

Before he moved what was then his Quicken Loans Inc. mortgage company downtown from Livonia into what is now the One Campus Martius building, whetting his appetite for central business district real estate, there had been talks about constructing a new Quicken headquarters on a portion of the property. 

That 300,000-square-foot, 10-story building referred to as 665 Atwater would have also included a 1,000-space-plus parking deck on the land bounded by Atwater to the south, St. Antoine to the west, Franklin to the north and Schweizer Place to the east. 

Then, when that fizzled, Gilbert and GM long had conversations about jointly building a mixed-use development on the site with office, residential and retail space. Obviously, to no fruition. 

Outside of and before its negotiations with Gilbert, in 2006, GM tapped Chicago-based real estate companies Mesirow Stein Real Estate Inc. and Morningside Equities Group to develop a 13-acre portion of the site into retail and residential space.

Ultimately, the GM, Mesirow Stein and Morningside plans fell through because “we couldn’t make economic sense of what GM and the city of Detroit were requiring … just the whole package of expectations regarding what would be built, who would build it, how it would get done, whether GM was going to be a partner, what they were demanding as their share of the development,” David Strosberg, president of Morningside, told me in 2015. “So it just stopped making sense.”

It’s not just during this century that visions for the site ultimately tanked. 

Even going back to the early versions of the RenCen, there had been grand visions for the complex to ultimately house a mind-boggling 18 towers, the Detroit Free Press reported in November 1971: A hotel, four office towers and 13 apartment buildings in a project that, when it was announced, was expected to take eight to 10 years to complete and cost $400 million to $500 million to build. By 1973, that plan had evolved into include the hotel and four flanking office towers, plus ten 19-story office towers and close to 1,000 apartments and condos spreading to the east of the current RenCen footprint, the Freep reported. 

Much of that scaled-down vision itself failed never materialized.

Ultimately, what we have today is the main first phase — a 73-story hotel tower flanked by four 39-story office towers — plus a second phase that includes two 21-story office buildings built in the early 1980s that are now under separate ownership from GM, and the land to the east remains undeveloped with a grand total of zero residential units on it. 

It could remain that way for a long time, too, even if Gilbert gets his hands on it through the put-and-call agreement. 

The agreement is just that — an option, not a foregone conclusion that a deal would happen. Both sides have the ability to compel the other to sell or buy under certain circumstances, but the agreement could be torpedoed if that’s what both parties want. 

There has been no formal determination on how GM and Bedrock will proceed with GM’s owned portion of the RenCen, which the automaker is vacating next year to move its headquarters into Gilbert’s $1.4 billion Hudson’s Detroit development north of Campus Martius Park. It could be redeveloped into new uses, or part or all of it could come down, creating more vacant riverfront land. Both of which have unknown costs, but suffice it to say that any option will come with a very large price tag. 

“We will continue to work with our partners to explore redevelopment opportunities for the Renaissance Center,” Kofi Bonner, CEO of Bedrock, said in an emailed statement on Tuesday afternoon. “As Mayor Duggan previously stated, this work takes time and we are exploring various possibilities, including redevelopment options for commercial, residential or mixed-use that will further enhance Detroit’s award-winning riverfront.”

Of course, the riverfront property to the east isn’t the only one Gilbert has had in his sights since emerging as the city’s most powerful developer and landlord the last 10-plus years. 

There are several large sites around town that Gilbert has controlled for years that have had development plans on the books that have not yet started.

Those include the 20-plus acres of the Brush Park neighborhood site best known as the former Brewster-Douglass housing projects, a property that prior to the pandemic had been planned for 900-plus units of mixed-income housing and some retail space. Nothing has yet been built there. 

In addition, the 14 or so acres of the former Wayne County Consolidated Jail property also sits undeveloped, having had two major proposals come and go: A Major League Soccer stadium with office, hotel and residential towers flanking it; and the University of Michigan Center for Innovation, which moved to a site in the District Detroit area and is now under construction. Most recently, the site had been proposed for a World Economic Forum project that would be part of what three years ago was a plan for new innovation center on the property at Gratiot Avenue and I-375. 

So whatever happens with 20 acres of key property south of Jefferson Avenue in terms of its ownership, it’ll likely be many years before anything is built there. 

Hopefully it’s not another 50.