Tainan City is located in the southwestern part of Taiwan's Jianan Plain, west of the Taiwan Strait, East Yili Mountain Range, north of Chiayi County, and South and Kaohsiung City. It is an important agricultural and sugar producing area in Taiwan. The old name of Tainan City, Chishao City, was originally reorganized into a “direct municipality” from Tainan County and Tainan City on December 25, 2010. The city has a population of 2,192 square kilometers and a population of approximately 1.87 million is the fourth largest city in Taiwan. The announcement pointed out that the Taipei County Restructuring Plan, the Taichung County Merger and Restructuring Plan, the Tainan County Merger and Restructuring Plan, and the Kaohsiung County Merger and Restructuring Plan came into effect on the same day; and since December 25, 2010, Taipei County was reorganized into New Taipei City, Taichung. The county and city were merged into Taichung City, Tainan County was merged into Tainan City, and Kaohsiung County was merged into Kaohsiung City. The city of each county was also converted into a district. On December 25, 2010, Tainan County was merged with Tainan City, a provincial city, and upgraded to a municipality. After the restructuring, it was 2,192 square kilometers and had a population of 1.87 million.