Ashgabat, the capital of Turkmenistan, holds the Guinness World Record for the highest density of white marble-clad buildings in the world. Following the country's independence from the Soviet Union, the city underwent a massive transformation, with over 500 high-rise buildings clad in luxury marble imported primarily from Italy. The city is also known for its eccentric monuments, including a giant gold-plated statue of the former president that rotates to always face the sun. Geographically, Ashgabat is located between the Karakum Desert and the Kopet Dag mountain range. Turkmenistan is also home to the 'Darvaza Gas Crater' (The Door to Hell), a natural gas field collapsed into a cavern that has been burning continuously since Soviet engineers lit it in 1971. The country is one of the most closed-off and least-visited nations in the world, maintaining a policy of strict permanent neutrality.