Kyrgyzstan is one of the Central Asian republics bordering Kazakhstan, China, Tajikistan, and Uzbekistan. It is a mountainous country—93% of its territory is located at over 1,000 meters above sea level. Lake Issyk-Kul, in the north-eastern Tian Shan, is the largest lake in Kyrgyzstan and the second largest mountain lake in the world after Titicaca. The highest peaks are in the Kakshaal-too range, forming the Chinese border. Peak Jengish Chokusu, at 7,439 m (24,400 feet), is the highest point and is considered by geologists (though not mountaineers) to be the northernmost peak over 7,000 m (23,000 feet) in the world. The history of the Kyrgyz people and the land of Kyrgyzstan goes back more than 2,000 years. Although geographically isolated by its mountainous location, it played an important role as part of the historical Silk Road trade route. In between periods of self-government, it was ruled by Göktürks, the Uyghur Empire, and the Khitan people, before being conquered by the Mongols in the 13th century. Subsequently, it regained independence but was invaded by Kalmyks, Manchus, and Uzbeks. In 1876, it became part of the Russian Empire, remaining in the USSR as the Kirghiz Soviet Socialist Republic after the Russian rule. Following Mikhail Gorbachev’s democratic reforms in the USSR, in 1990, pro-independence candidate Askar Akayev was elected president. On 31 August 1991, Kyrgyzstan declared independence from Moscow, and a democratic government was subsequently established.