Aspire Tower, also called The Torch Doha, is a 300-metre-tall (980 ft) skyscraper hotel located in the Aspire Zone complex in Doha, Qatar. Designed by architect Hadi Simaan and AREP and engineer Ove Arup and Partners, the tower served as the focal point for the 15th Asian Games hosted by Qatar in December 2006.
The Willis Tower (formerly and informally: Sears Tower, its title until 2009) is a 110-story, 1,450-foot (442.1 m) skyscraper in Chicago. At completion in 1973, it surpassed the World Trade Center in New York City to become the tallest building in the world, a title that it held for nearly 25 years; it was also the tallest building in the Western Hemisphere for 41 years, before the new One World Trade Center surpassed it in 2013. While it held the title of'Tallest Office Building' before 2013, it dropped the title of'Tallest Man-Made Construction' after only 3 decades. The CN Tower in Toronto, which functions as a communications tower, took over the title in 1976. The Willis Tower is considered a seminal accomplishment for engineer Fazlur Rahman Khan. It is currently the third-tallest construction in the USA and the Western hemisphere -- and the 23rd-tallest in the world. Annually, several million people visit its observation deck, the highest in the USA, which makes it one of Chicago's most popular tourist destinations. The arrangement was renamed in 2009 by the Willis Group as a term of its lease. As of April 2018, the building's largest tenant is United Airlines, which moved its corporate headquarters in 77 West Wacker Drive (then the United Building) in 2012, occupying around 20 flooring. Other major tenants include the building's namesake Willis Towers Watson and law firms Schiff Hardin and Seyfarth Shaw. Morgan Stanley plans to move into the construction in 2019 and become its fourth-largest tenant by 2020.Source: Wikipedia