arabianbusiness.com — Saudi Prince Al-Waleed bin Talal says he will build the world's tallest building in the city of Jeddah. It will be more 1.2 kilometers (3,937 feet) high and will be part of a larger project that will cost 100 billion riyals ($26.7 billion), span 23 million square meters (248 million square feet) and include luxury homes, hotels and offices.