Bao'an (Chinese 宝安 区, Pinyin Bǎo'ān qū) is the largest of the ten municipalities of the Chinese city of Shenzhen. The district is located outside the Special Economic Zone in the northwest of the city adjacent to the districts of Nanshan, Futian, Luohu and Longgang. These are mainly migrant workers from Guangdong and neighboring provinces. As there are generally a large number of migrant workers living in the district and also the other parts of Shenzhen, it was only possible to make very few inaccurate figures about the number of inhabitants before the census in 2010, which included these. There was an official figure in 2003 that 310,000 people had their main residence in Bao'an. Also very important for the region is the Shenzhen International Airport (SIA) located in the district.