In 1998, Pittsburgh's last operating steel mill closed, leaving 178 riverfront acres vacant; 28 years later, 700,000 sq ft has been built or is underway for robotics, biotech, housing and parks

• The new CMU Robotics Innovation Center sits in the foreground, with new housing development under construction behind it and the U.
• Steel Community football field visible in the background.
• For decades, 178 acres along the Monongahela River in Pittsburgh remained largely vacant after the collapse of the steel industry.