Timeframe: when Burj Khalifa was still a construction site

Burj Khalifa may tower over the city of Dubai now , but this time in 2005 the structure of the skyscraper had only just begun rising on the Downtown Dubai site, seven months after construction began on September 21, 2004. It would be three years until the building surpassed the KVLY-TV mast in North Dakota to become the tallest man-made structure in the world in April 2008. The milestone was achieved when level 160 of Burj Khalifa was reached, it was 629 metres tall. Five months later it was announced that the building had reached 688m, surpassing the Warsaw Radio Mast in Poland as the tallest man-made structure ever built. The previous record-holder was 646.38m but collapsed in August 1991. The vertical climb of Burj Khalifa topped out at 829.8m, with 163 floors, on January 17, 2009. On October 1, 2009, Emaar announced that the exterior was completed. Three months later, the building officially opened on January 4, 2010. While under construction, the tower was known as Burj Dubai. The new name, honouring President Sheikh Khalifa, was announced at the official launch ceremony. In March 2010, the Council on Tall Buildings and Urban Habitat officially named Burj Khalifa as the world's tallest building, which it remains to this day. “Burj Khalifa has redefined what is possible in the design and engineering of supertall buildings. By combining cutting-edge technologies and cultural influences, the building serves as a global icon that is both a model for future urban centres and speaks to the global movement towards compact, liveable urban areas,” the CTBUH says of the building. "[Its] architecture has embodied references to Islamic architecture and yet reflects the modern global community it is designed to serve.” The construction of Burj Khalifa ran in parallel with the building of The Dubai Mall , which opened in November 2008. Speaking of the wider project, Robert Booth, executive director of Emaar Properties at the time, told AFP in April 2005: “It's probably the best located piece of land in all of Dubai. It is what it is today because it was a military base for 30 years. It's the heart of all of the major high-density area.”