1378.4 km. According to Baidu map, it takes1.378.4km to reach Vientiane from the first city in the south of Dongguan, and the whole journey takes 1.4 hours and 49 minutes, via the Economic Guangzhou Expressway and the Shanghai-Kunming Expressway. The first city in the south of the Yangtze River is located atNo. Jinfeng Road 10, Chengnan District, a residential area planned and developed by Guangdong Hongyuan Group Real Estate Development Company.