<P> Aria was conceived by MGM Mirage (now MGM Resorts International) as part of the broader CityCenter development project, which was announced on November 10, 2004 . The architectural design of Aria was conducted by Pelli Clarke Pelli Architects, and construction began in early 2006 on a plot of land located between the Bellagio and Monte Carlo . This site was previously occupied by the former Boardwalk Hotel and Casino, retail stores, and a large parking lot, all of which were excavated beginning in April 2006 . Following excavation, Aria's foundation was poured in June 2006 . Vertical progression commenced in September 2007, at which point construction workers built upwards at a rate of one floor every seven days until reaching the final height of 61 floors . </P> <P> Amid ongoing construction in 2007, Infinity World Development, a subsidiary of Dubai World, invested about $2.7 billion to acquire a 50% stake in the CityCenter project . From this point on, Aria was jointly owned by MGM Resorts International and Infinity World Development, with MGM solely responsible for operations and management . The economic downturn and its ripple effects--including litigation--threatened to halt construction of Aria at one point in early 2009, but an additional funding arrangement was made, allowing construction to continue on schedule . The resort opened on December 16, 2009, in the same month as several other CityCenter properties such as The Crystals, an attached retail shopping complex . </P> <P> The completed structure comprises two curvilinear glass towers, measuring 61 stories tall . At the base of the connected high - rise towers is a casino and a three - story lobby that incorporates natural materials including foliage, flowers, glass, wood, and stone . Aria's design is described as not adhering to an overarching theme, in contrast to themed resorts prevalent on the Las Vegas Strip . It was named Aria due to its placement as the central feature of CityCenter, as arias are focal points in operas . </P> <P> Artwork is incorporated throughout the lobby and interior of the building . The main entrance contains a lighted water feature called "Lumia" which syncs water bursts to music . Maya Lin, designer of the Vietnam Veterans Memorial in Washington, D.C., created an 87 ft (27 m) reclaimed silver sculpture of the Colorado River called Silver River which is suspended behind Aria's hotel registration desk . A result of its design, Aria is the largest hotel in the world to have received LEED Gold certification . </P>

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