Thimphu contains most of the important political buildings in Bhutan, including the National Assembly of the newly formed parliamentary democracy and Dechencholing Palace, the official residence of the King, located to the north of the city. As a metropolis and capital city, Thimphu is coordinated by the "Thimphu Structure Plan", an Urban Development Plan which evolved in 1998 with the objective of protecting the fragile ecology of the valley. This development is ongoing with financial assistance from the World Bank and Asian Development Bank. The culture of Bhutan is fully reflected in Thimphu in respect of literature, religion, customs, and national dress code, the monastic practices of the monasteries, music, dance, literature and in the media. Tsechu festival is an important festival when mask dances, popularly known as Cham dances, are performed in the courtyards of the Tashichhoe Dzong in Thimphu. It is a four day festival held every year during autumn (September/October), on dates corresponding to the Bhutanese calendar.