Kuala Lumpur is located in the heart of Selangor State. It is bordered by mountains on all sides, except in the east, which is why Kuala Lumpur and adjacent areas are called the "Klang Valley". The city was once the residence of the federation's executive and judicial powers, but they have moved to Putrajaya since 1999. The city is also the cultural and economic center of Malaysia, due to its position as the capital, as well as and being a city of the first size. Over the past few decades, Kuala Lumpur has become a thriving metropolis with spectacular buildings such as the Petronas Towers.