Sakai City is located in the southern part of Osaka prefecture. Famous throughout history as an early center of Japanese civilization (the tumuli of various early Japanese emperors, including Nintoku, are located in Sakai City) as well as for its early trade with the West, Sakai today stands almost as an extension of Osaka City which borders it.

Demographically, it has a population of 797,827 people (September 1, 1997 data) of which 389,399 are male and 408,428 are female. It has a population density of 5,832 people per square kilometer.

Sakai City has an area of 136.79 square kilometers (52.81 square miles). It is bordered by Osaka, Matsubara, and Izumi cities. It also is fronted by the Pacific Ocean and boasts of a port which can handle container shipments.

On the stage of history, Sakai was where the famed Zen teamaster, Sen-no-Rikyu lived and later committed suicide in protest against the government. It is also where the Jesuit priest, Frances Xavier landed during his mission to Japan. This led Sakai, together with Nagasaki, to become one of the two major trading ports in the early exchanges with the West. Always a city of industry and growth, Sakai suffered during World War II when it was heavily bombed in efforts by the U.S. forces to destroy the heavy equipment factories located in the city. Most recently, Sakai has become infamous as the city in which the food poisoning epidemic caused by 0-157 occurred after school children were fed contaminated school lunches during the summer of 1996.