DUBAI, United Arab Emirates: Dubai is set to open the world's tallest building amid tight security today.

The tower is being celebrated as a bold feat on the world stage, despite the city state's shaky financial footing.

But the final height of the Burj Dubai - Arabic for Dubai Tower - remains a closely guarded secret on the eve of its opening. At more than 800 meters, it long ago vanquished its nearest rival, the Taipei 101 in Taiwan.