KL is the national capital of Malaysia as well as its largest city. The only alpha world city in Malaysia, it covers an area of 243 km2 (94 sq mi) and has an estimated population of 1.73 million as of 2016. Greater Kuala Lumpur, also known as the Klang Valley, is an urban agglomeration of 7.25 million people as of 2017. It is among the fastest growing metropolitan regions in South-East Asia, in both population and economic development.