This 4 minute YouTube video shows a timelapse of the construction of a large skyscraper in downtown Chicago over the course of a year. Workers are seen building the steel framework for the high-rise building floor by floor using cranes as the building rises higher into the sky. By the end of the timelapse, the skyscraper is complete with windows installed and exterior cladding finished, culminating over a year of intensive construction work to erect another tall building in Chicago's skyline.