Turkmenistan, formerly known as Turkmenia, is one of the Turkic states in Central Asia. Turkmenistan is bordered by Kazakhstan to the northwest, Uzbekistan to the northeast and east, Afghanistan to the southeast, Iran to the south and southwest, and the Caspian Sea to the west.Present-day Turkmenistan covers territory that has been at the crossroads of civilizations for centuries. In medieval times Merv was one of the great cities of the Islamic world, and an important stop on the Silk Road, a large road used for trade with China until the mid-15th century. Annexed by the Russian Empire in 1881, Turkmenistan later figured prominently in the anti-Bolshevik movement in Central Asia. In 1924, Turkmenistan became a constituent republic of the Soviet Union, Turkmen Soviet Socialist Republic; it became independent upon the dissolution of the Soviet Union in 1991.Turkmenistan's GDP growth rate of 11% in 2012 comes on the back of several years of sustained high growth, albeit from a very basic undiversified economy powered by export of a single commodity. It possesses the world's fourth largest reserves of natural gas resources. Although it is wealthy in natural resources in certain areas, most of the country is covered by the Karakum Desert.Turkmenistan was ruled by President for Life Saparmurat Niyazov until his sudden death on 21 December 2006. Gurbanguly Berdimuhamedow was elected the new president on 11 February 2007.