Hiroshima Sun Plaza (åºÂå³¶ãµã³ãÂÂã©ã¶) is an arena in Hiroshima, Japan. With a capacity of 6,052, it is primarily used for indoor sports and concerts. In addition, the annual Seijin shiki (the Japanese coming-of-age ceremony) is held there every January, sponsored by the Hiroshima City government.