As of Feb. 1, 2015, the city had an estimated population of 28,960 and a population density of 785 persons per km². The total area is 36.91 km².
The city was founded on May 1, 1956, when the neighbouring four towns of Minoshima, Miyazaki, Yasuda and Miahara merged to form a single city. The main industries in Arida and the surrounding areas are oil refining and fishing. In addition, Arida is famous as one of the largest producers of mikan or Japanese mandarins in Wakayama Prefecture. Arida's sister city in the US is Delano, California.