The popuration of Awaji Island is 152,791. Awaji Island consists of the three cities of Awaji, Sumoto and Minami Awaji. Located in the eastern portion of the Seto Inland Sea, it is across the Akashi Strait from Mainland and across the Naruto Strait from Shikoku. The Higashiura coast faces Osaka Bay, Nishiura coast faces Harimanada, and the Nada coast faces the Kitan Strait. Awaji Island is a narrow island that runs 55 km north-south (Awaji City Matsuho - Minami Awaji City Numajima), 28 km east-west (Sumoto City Yura - Minami Awaji City Anaga) and is 203 km in circumference.The 135-degree east meridian that determines Japan Standard Time runs through the northern portion of the island that contains the Awaji Yumebutai International Conference Center. With 595 km2 area, Awaji Island accounts for 7.1 percent of the total area of the prefecture, and is the largest island in the Seto Inland Sea. The island is smaller than Lake Biwa, is about the same size as Singapore, and is a little large than Guam. It is the seventh largest island in Japan.

Mountains and hills take up about 65 percent of the island. Sloping areas are being turned into farmland. Scenic rice terraces decorate the former Hokudan-cho and the skirts of religious place (Mt. Sen). The island is also blessed with water. Because there are no high mountains that serve as a source of water, the island is characterized by an abundance of reservoirs. The island depends on reservoirs for water for agriculture more than rivers. It is said there are about 25,000 reservoirs on the island. Extending from the center to the southern portion, the Mihara Plain is the largest flat land area on the island. Sumoto River and Mihara River runs through it.

In the south, the Yuzuruha mountain land that contains Mt. Yuzuruha (608m), the highest peak on the island runs east-west, forming the coastline of steep cliff. Nushima is located 4 km off the coast of the main island. The Naruto Bridge opened in June 1985, the Akashi Kaikyo Bridge in April 1998, uniting Awaji Island with Honshu and Shikoku.

The island has a Seto Island Sea climate. Winters are mild and there is almost no snowfall. The summer is about as hot as other areas. There is no "heat island” phenomenon at night, and the summer is comparatively mild. The island is warm throughout the year - the average temperature is 15.1°C. The seasonal wind is however very strong on the Nishiura coast in the winter; it reminds one of the winter on the Sea of Japan coast.

There is little rainfall, so there is often a shortage of water. Reservoir have been constructed since ancient times. In modern times, many dams have been constructed, and water piped in from the mainland was realized with the opening of the Akashi Kaikyo Bridge.

The island is not on the typhoon course like Okinawa and South Kyushu during the typhoon season from August to September, but typhoons traveling north from the eastern part of Shikoku and the Kii Penninsula affect Awaji significantly and have resulted in huge disasters many times.

The large-scale whirlpools cased by the difference in ebb and flow of tides from the Seto Inland Sea (Harimanada) and Pacific Ocean (Kii Waterway) can be seen in the Naruto Strait that separates Awaji and Tokushima. Awaji Island also has a unique coastline. Facing Harimanada, there is Keino Matubara, which is designated as a national scenic spot and Narugashima sand bar Sumoto on the opposite shore from Yura Fishing Port of Sumoto City.

There are many dominant species of tropical natural forests, and there are still virgin akagashi (quercus acuta) forests consisting of akagashi and sudajii (castanopsis cuspidate). Rare seaside beach such as Hibiscus hamabo of Narugashima are also widely distributed.

The island’s fauna includes mammals such as deer, wild pigs, Japanese monkeys, and raccoon dogs, as well as a profusion of wild birds such as white-eyes, plovers, and black-tail gulls. The fact that the only Japanese monkeys in the Seto Inland Sea area live on Awaji Island and Shodoshima is testimony to the richness of the natural environment of Awaji.

[ National Monuments of Awaji Island ]