In August 2008, China's first high-speed railway, the Beijing-Tianjin Intercity Railway, with a speed of 350 kilometers per hour was opened. In August 2008 Tianjin was the co-host city of the 29th Olympic Games. In September 2008, the Annual Meeting of the New Champions of World Economic Forum (also called Summer Davos) began to be established in Tianjin and is held every two years.[23] In October 2010, the UN Climate Change Conference convened in Tianjin.[24] In 2012, the Tianjin Metro Lines 2, 3, and 9 were completed and open to traffic, and Tianjin Rail Transit was formally networked.