Burj Khalifa (Arabic: برج خليفة, "Khalifa Tower") is an extremely tall skyscraper in Dubai, United Arab Emirates named after Khalifa bin Zayed Al Nahyan, and is the tallest building ever built, at 828 metres (2,717 feet). Before the building opened, it was called Burj Dubai. The building is 162 stories high. Construction of the tower was started in 2004. The building was officially opened on 4 January 2010. It is the tallest structure made by humans in the world. The building is more than 300 metres (980 feet) taller than Taipei 101. Taipei 101 was the tallest building until 2010 before Burj Khalifa was built. Adrian Smith designed the tower. He worked with Skidmore, Owings and Merrill (SOM) until 2006. It was built by Samsung Engineering & Construction, Besix, and Arabtec. The tower cost US $1.5 billion to build.The building is part of a 2 kilometres (1.2 miles) building project on Sheikh Zayed Road, Downtown Burj Khalifa. It is near Dubai's main business district. The main contractor was Samsung C&T of South Korea. They also built the Taipei 101 and Petronas Twin Towers. Other contractors who helped with the building included Belgian group Besix and Arabtec from the UAE. The Turner Construction Company was chosen as the construction project manager. The design architect, Adrian Smith, did not like the first design of the upper part of the building. He added 27 new floors and an aluminium spire to the top of the plans. The design of Burj Khalifa based on those used in Islamic architecture. Burj Khalifa has been said to have had several other planned height increases since it was first built. This has not been proven to be true yet. The TV/radio communications mast was added to the tower's plans in 2007. This was after building work had begun in 2006. There are pressurized, air-conditioned refuge floors about every 35 floors. These were put into the tower in case of an emergency or fire.