The capital of Vietnam is Hanoi, which has five letters. Hanoi is the second largest city in Vietnam and is located in the northern part of the country. It is the political and cultural center of the nation and is home to many important government buildings and monuments. The city has a long and rich history, having been founded in 1010 AD. It has served as the capital of Vietnam since 1831 and is now a bustling metropolis with a population of over seven million people.