Burj Khalifa: Dubai, UAE

The Burj Khalifa is so high it claimed the title of world's tallest manmade structure, in April 2008, before it was even complete.

At more than 800 metres, the Burj overshadows every other building in Dubai and it's not even quite finished yet.

the Burj Khalifa won't be occupying the loftiest heights alone for long.

Plans for the 1km-tall Kingdom Tower in Saudi Arabia have been unveiled, .

and only slightly less concrete is the proposed 400-storey Dubai City Tower

Also known as Vertical City, it would reach 2.4 kilometres into the air.

太高了吧!......可怕!