Dubai opened the world's tallest structure yesterday in a glitzy ceremony putting a brave face on crushing debt woes and leading some to wonder whether the tower is the emirate's crowning glory or its last hurrah. [coverage about Dubai debt crisis]

The US$1.5 billion tower reaches 828 meters, 200 stories into the sky, exceeding the next highest structure, Taipei 101, by about 300m.

Dubai's ruler Sheikh Mohammed bin Rashid al-Maktoum renamed the tower Burj Khalifa after the president of the United Arab Emirates and the ruler of the neighboring emirate of Abu Dhabi, Sheikh Khalifa bin Zayed al-Nahayan.

Abu Dhabi has provided US$25 billion in bailout funds for Dubai in the past year, fueling expectations that Dubai will make concessions or cede some of its commercial power to its neighbor.

Concerns about Dubai's US$100 billion debt pile, which has made its stock exchange one of the world's worst performing, overshadowed the ceremony and boasts by the builder, Emaar Properties, that the Burj heralds a new dawn.

"The worry for Dubai is that the event will be remembered as a second bout of hubris," said David Butter, regional director for the Middle East and North Africa at Economist Intelligence Unit.

The first bout was in November 2008, two months after the collapse of Lehman Bros, when Dubai spent US$24 million on the opening ceremony of the Atlantis Hotel, an event that did more to highlight a taste for extravagance than assuage fears that the economic crisis was not being taken seriously.

Emaar said property prices had now stabilized, confounding wider expectations for stress in the sector.

"You have to ask, 'why we are building all this?' To bring quality of life and a smile to people and I think we should continue to do that," said Mohamed Alabbar, chairman of Emaar, the Arab world's largest listed developer.

"Crises come and go," Alabbar told reporters. "We build for years to come ... We must have hope and optimism."

From the 124th floor observation deck of the tower, viewers can see 80 kilometers on a clear day.

The air is noticeably cooler and fresher on the terraces compared to the stifling heat and humidity at ground level during Dubai's summer.

Terraces are located at setbacks spiralling up the tapered tower, which is based on the "geometries of the desert flower and the patterning systems embodied in Islamic architecture," according to its promotional literature.