The urban conservation in Thailand became the public interest since the last two decades. In 2005 , the government has made ‘Regulations ofthe of ce of the prime minister on Rattanakosinand old cities Conservation and DevelopmentPlan’ with an announcement of the rst 10 herit- age cities to be a pilot site. Nan was selected among the 10 heritage cities that has been announced to bethe rst priority cities withan outstanding Lanna ar- chitecture and their culture richness that still maintain.

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            The World Health Organisation (WHO) has suggested that every city should have a minimum of 9 square metres of green space per person. At this time Nan only has 4.9 square metres of green space per person which will grow up to 16 square metres per person after the project construct.

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