The ARIA resort at CityCenter on the Las Vegas strip opened December 16 with a lavish fireworks display to mark the completion of the most expensive private construction project in US history.

The ARIA Resort and Casino includes 568 suites, 16 restaurants, nine bars, 1,940 slot machines and 13,935 square meters (150,000 square feet) of gaming space. It is the ninth largest hotel in the world by room count, adding 4,004 rooms to the already competitive Las Vegas market. Room rates in the city averaged a record low of $84 (€58) a night in 2009, down from $115 (€80) in 2008, according to online booking site

Nevertheless, the partners behind the venture, MGM Mirage and Dubai World, have high hopes that the project can reinvigorate Las Vegas's ailing tourism business. The hotel claims to have the most technologically advanced guestrooms in the US, with rooms that 'greet' the visitor by opening curtains, programmable light 'scenes' and a 42-inch HDTV in every room. CityCenter also boasts the largest Distributed Antenna System in the world, covering 1.3 million square meters (14 million square feet) with wifi using more than 6,500 antennas and 2,900 wireless access points.

Despite this technological wizardary, ARIA has also been keen to champion its green credentials - the hotel will operate the world's first fleet of stretch limousines powered by compressed natural gas and its slot machines feature bases that serve as ventilation units, cooling guests from the ground up instead of from the ceiling. The hotel is the largest building in the world to achieve LEED (Leadership in Energy and Environmental Design) Gold Certification by the US Green Building Council.

"CityCenter captures the energy and diversity of Las Vegas in one of the world's largest green developments," said Jim Murren, chairman and CEO of MGM Mirage. "Designing CityCenter with sustainable elements and practices reinforces its permanence and creates a healthier environment for our guests and residents, as well as for the 12,000 people who work at CityCenter."

CityCenter, which houses ARIA along with three other hotels, a shopping mall and residential buildings is reported to have cost around $14 billion (€9.7 billion) and will employ 12,000 staff.