The development firm HYM Investment Group is expected on Friday to close on its purchase of the all-but-shuttered horse track for $155 million and will begin turning the 161-acre site into East Boston’s answer to other mega-developments such as Assembly Row and Boston Landing — only much bigger.
The new owners envision a vast complex of housing, shops, restaurants, and eventually offices, arranged on pedestrian-friendly city blocks.
It would be perhaps the largest single development in urban Boston, and will probably cost in the billions to fully build out over a decade or more, said HYM’s managing director, Tom O’Brien. He has few specifics just yet, but points to the successful Assembly Row complex in Somerville as an example of the type of project he has in mind for Suffolk Downs.