Japan's island geography means that even inland cities have offshore islands accessible by a short ferry or causeway. Many of Japan's most memorable day trips involve the particular pleasure of crossing water — the transition from mainland to island carrying a sense of arrival unique to insular destinations.
Near Tokyo
Sarushima (Monkey Island, Kanagawa): Japan's only natural uninhabited island in Tokyo Bay — accessible by ferry from Yokosuka (10 minutes, ¥1,300 return). Brick fortifications from the Meiji era, swimming in clear water, and zero commercial development. Open only in warm months. Nokogiriyama (Chiba): Not strictly an island but a mountain peninsula accessed by ferry from Kurihama (¥770 return) — giant carved Buddha faces in cliff faces, mountain hiking, and views across Tokyo Bay. Enoshima (Kanagawa): Dragon shrines, sea caves, and shirasu seafood, covered in its own guide.
Near Osaka/Kobe
Awaji Island: Connected by the Akashi Kaikyo Bridge (the world's longest suspension bridge), Awaji is technically reachable by car or bus without a ferry. The island produces Japan's best onions, has excellent onsen resorts, and the Uzushio whirlpools off its southern tip are accessible by sightseeing boat. Teshima and Naoshima: Art islands in the Seto Inland Sea accessible from Takamatsu or Uno (Okayama) by ferry.
Near Hiroshima
Miyajima (Itsukushima): The famous floating torii gate island — deer roam freely, Itsukushima Shrine is a UNESCO World Heritage site, and the mountainous interior offers hiking to the summit of Mount Misen for panoramic views over the inland sea. Ferry from Miyajimaguchi: 10 minutes, ¥200. Ohkunoshima (Rabbit Island): Covered in its own guide — accessible from Tadanoumi ferry terminal.
Ferry Tips
Japanese ferries are almost universally punctual to the minute — check departure times and arrive 5 minutes early. IC cards (Suica/Pasmo) are increasingly accepted on short ferry routes. Round-trip tickets are usually available at slight discount. Most island ferries have no food service — buy food on the mainland for the journey.
