Vientiane (Lao The great Laotian epic, the Phra Lak Phra Lam, claims that Prince Thattaradtha founded the city when he left the legendary Lao kingdom of Muong Inthapatha Maha Nakhone because he was denied the throne in favor of his younger brother. Thattaradtha founded a city called Maha Thani Si Phan Phao on the western banks of the Mekong River; this city was told to have later become today's Udon Thani, Thailand. One day, a seven-headed Naga told Thattaradtha to start a new city on the east… (More on Vientiane)