Soon after the completion of the 973-foot-tall Comcast Center in 2008, which stood as the tallest building in Philadelphia, local residents and outside watchers wondered what was next for the city skyline. Almost six years later, on January 15, 2014, the design for the Comcast Technology Center, then known as the Comcast Innovation and Technology Center, was revealed to the public. The tower would become the new tallest skyscraper in Philadelphia, planned to stand 1,121 feet tall at 1800 Arch Street in Center City, across the street from the previous record-holder. The design by Foster and Partners was an unfinished version of the current building, as many portions of the building had to be finalized. The developer of the Comcast Technology Center is Liberty Property Trust, which met its fate when it was purchased by Prologis Inc. In this YIMBY feature, we compare the 2014 design and the current version of the skyscraper using renderings, architectural models, and photographs.