Bangkok is the capital, largest urban area and primary city of Thailand. Known in Thai as Krung Thep Maha Nakhon, meaning "city of angels" for short, it was originally a small trading post on the west bank of the lower Chao Phraya River during the Ayutthaya Kingdom. It became the capital in 1768 after the destruction of Ayutthaya by Burmese invaders. However, the current Rattanakosin Kingdom did not begin until 1782, when the capital was moved to the east bank of the river by Rama I following the death of King Taksin. The city is more formally called Phra Nakhon, referring to the original boundaries of the 18th century, while the name Krungthep Mahanakorn includes the urban areas which have since grown. Foreigners generally call the city by its original name of Bangkok.