Shikoku is the smallest of Japan's four main islands, covering roughly 18,800 km² with a population of about 3.5 million. It sits south of Honshu across the Seto Inland Sea, connected by the Great Seto and Akashi Kaikyo bridge systems, and is divided into four prefectures: Ehime (capital Matsuyama), Kagawa (capital Takamatsu), Kochi (capital Kochi), and Tokushima (capital Tokushima).
The island is best known for the Shikoku Henro, an 88-temple Buddhist pilgrimage circuit associated with the monk Kukai (Kobo Daishi) that loops roughly 1,200 km around the island's perimeter — still walked in part or in full by thousands of pilgrims each year, recognisable by their white robes and conical sedge hats. Kagawa prefecture is also famous within Japan as the birthplace of sanuki udon, and Tokushima hosts one of the country's largest Awa Odori dance festivals every August.
Beyond the coastal cities, the interior is mountainous and sparsely populated — the Iya Valley in Tokushima prefecture is one of Japan's most remote inhabited regions, known for its vine bridges and steep terraced villages, in sharp contrast to the industrial coastal strip along the Seto Inland Sea.
