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Tran Temple Festival, one of the largest annual spring festivals in Vietnam, is held on the 14th night and 15th day of the first lunar month at the national historical complex of the Tran Kings shrines and tombs in Tien Duc Commune, Hung Ha District, Nam Dinh City. It usually begins with an incense-offering rite at the kings' tombs and a ritual for the opening of the gates of Den Thanh (Thanh Temple), Den Mau (Mother Temple) and the Tran Kings' shrines. They are followed by a 'water procession', in which people will carry nine ornate palanquins with memorial plaques of the Kings of the Tran Dynasty and members of their royal families. A series of folk games are also organized during the festival, such as a rice-cooking challenge, clay firecrackers, chung cake wrapping and tug of war, alongside traditional performances and sport games including lion dances, dragon dances, cheo and chau van singing, human chess, wrestling and martial arts. The Tran Temple Festival was recognized as a national intangible heritage in 2014. The historical complex of the Tran Kings' shrines and tombs received special national relic status last year.
1. What are they followed by?