The island has a length of and a width of. The highest point of the island measures in elevation. The total area of the island is approximately. Although called it is an island, it is connected to the mainland by a causeway constructed in 1942 so that people may walk to it from the shore.
is a small Shinto shrine located on Kabushima island. The shrine is a branch of the Itsukushima Shrine and is dedicated to Benzaiten. According to shrine legend, it was established in 1269 by local fishermen. The shrine burned completely down on 5 November 2015, but it was rebuilt and expanded at the cost of 5 billion yen. The shrine reopened on 26 March 2020 after a small reopening ceremony. The ceremony was scaled down due to the COVID-19 pandemic. The main festival of the shrine is held on the third Sunday of April.