Yakushima: The Rain-Soaked Island Where Japan's Oldest Cedars Still Stand

Updated October 15, 2026 | By Tokyo Paul

Picture a granite island rising out of the sea south of Kyushu, its peaks wrapped in cloud, its slopes crowded with trees that were already ancient when the first samurai drew a sword. That is Yakushima (屋久島), a roughly round island of about 500 square kilometers in Kagoshima Prefecture. Its summit, Mount Miyanoura (Miyanoura-dake), climbs to roughly 1,940 meters, the highest point in Kyushu, which is a great deal of mountain for an island you can drive around in about three hours. Warm ocean air meets those slopes, rises, cools and falls as rain, and the rain feeds a forest unlike any other in Japan.

UNESCO added Yakushima to the World Heritage list in 1993, protecting 10,747 hectares, around a fifth of the island. This guide covers what makes the place special: the famous Jomon Sugi cedar, the mossy ravine that many people connect with Princess Mononoke, the weather you should plan around, how to get there, and the trail rules that matter. Yakushima rewards preparation more than almost any other destination in Japan, and it rewards patience even more. Rain is not a flaw here. It is the reason the forest exists at all.

The Island Built by Rain

The famous line about Yakushima is that it rains 35 days a month. No month has 35 days, so the joke is the point: the rain feels endless. The saying is often credited to the novelist Hayashi Fumiko and her book Ukigumo (Floating Clouds), though sources differ on that. The numbers behind the joke are real enough. According to a Japanese land ministry multilingual page, the coastal town of Nagata averaged about 1,377 millimeters of rain in 2017, while mountain stations recorded roughly 5,700 and 7,000 millimeters. UNESCO describes totals above 8,000 millimeters in places, so figures vary by year and location.

The cause is geography. The Kuroshio Current feeds warm, moist air toward an island whose peaks climb nearly 2,000 meters, and the air has nowhere to go but up, where it cools and drops its water. About half of the year's rain falls between May and August, and typhoons can pass nearby from roughly July to October. The east side tends to be wetter than the south and west. None of this means a trip is doomed. Clear mornings do happen, and mist on a cedar trunk makes a better photograph than blue sky. It just means your plan needs some slack in it.

Yakusugi: Cedars That Outlast Empires

Yakushima's cedars have their own name. A Japanese cedar (sugi) that is more than about 1,000 years old is called a yakusugi (屋久杉), and UNESCO notes that some of the island's trees are thousands of years old. Slow growth is the secret. The granite soil is thin, the highlands are cool and damp, and the trees add rings at a crawl, producing wood so resinous that it resists rot. That same quality drew loggers for centuries, and giant stumps from old harvests still sit in the forest. Younger island cedars are called kosugi, so a guide may point at a very large tree and call it a baby.

The forest holds more than trees. Yakushima macaques and sika deer are the only large native mammals on the island, and the local deer are noticeably smaller than their mainland cousins. UNESCO counts about 1,900 species and subspecies of plants, 16 mammal species and 150 bird species in the protected area. The climb from coast to summit also changes the landscape from warm, subtropical growth near the sea to cool, misty highland forest, so a single long hike can feel like crossing several climates. Expect to see monkeys on the roads and deer on the trails, and give both plenty of room.

Jomon Sugi and the Long Walk to Meet It

The most famous tree on the island is the Jomon Sugi (縄文杉), named for the Jomon period of prehistoric Japan. It stands about 25 meters tall with a girth of around 16 meters. Age estimates swing from at least 2,000 years to as many as 7,200, and the size of that range tells you nobody is certain. Whatever its true age, it is widely described as the oldest tree in Japan. Its twisted, knobbly shape probably saved it from the loggers. It was officially identified in 1966, and the attention it drew helped build the case for protecting Yakushima's forests.

Meeting the tree takes effort. The standard route starts at the Arakawa trailhead and runs about ten hours round trip, so most people set out before dawn to be back by sunset. Part of the way follows the Anbo trail beside an old railway line, flat and easy underfoot, before boardwalks and wooden steps climb toward the tree. Along the route you pass Wilson's Stump, the remains of a huge cedar cut in the 1580s, and Meoto Sugi, a pair of trees that seem to embrace. At the end you view the Jomon Sugi from an observation deck about 15 meters away, built to protect its roots.

Shiratani Unsuikyo and the Mononoke Question

If ten hours sounds like too much, Shiratani Unsuikyo (白谷雲水峡) is the gentler answer. This ravine park of streams, granite boulders and mossy cedar forest has marked circuits of roughly one to five hours, with English signs along the way. Admission has been around 800 yen (about $5), and the park is open every day. The Kugurisugi, a cedar you can pass beneath, is only about a 15-minute walk from the entrance. Farther in, boardwalks, stone steps and an old Edo-period footpath lead through trees furred with moss so thick that it seems to soften every sound.

Shiratani is the place most people link to Princess Mononoke (もののけ姫), Studio Ghibli's 1997 film. The connection is popular, and a small grove near the far end of the park is nicknamed the Mononoke forest, but it pays to be careful. Travel guides describe the forest as an inspiration for part of the film, and they say the film's mountains also drew on the Shirakami-Sanchi range in Akita Prefecture. Treat the link as a lovely resonance rather than a documented map. You do not need the movie to feel it. The green light, dripping water and silence do the work.

Getting to Yakushima and Getting Around

Yakushima is reachable, but it is a real journey. From Tokyo, the usual route is a flight from Haneda to Kagoshima Airport (about two hours) and a connecting flight to Yakushima Airport (about 40 minutes), which Japan's national tourism organization puts at roughly three hours in total. Alternatively, a high-speed jetfoil from Kagoshima Port to Miyanoura or Anbo takes around two to three hours and has cost about 12,700 yen one way (roughly $85), while the slower car ferry takes about four hours at around 6,000 yen. Fares and timetables change, and winter sailings are fewer, so confirm before you book.

On the island, buses are infrequent, and the road around the coast takes about three hours to drive, so many visitors rent a car or book guided hikes that include hotel pickup. Miyanoura and Anbo are the two main ports, and the Yakusugi Museum (Yakusugi Shizenkan) is the departure point for the Arakawa trail shuttle. Because ferries and flights can be canceled in rough weather, add a spare day at the end of the trip if you have an onward flight to catch from Kagoshima or Tokyo. A tight schedule is the one thing this island does not forgive.

Trail Rules, Guides and What to Pack

Between March and November, private cars are not allowed on the access road to the Arakawa trailhead. You ride a shuttle bus from the Yakusugi Museum instead, which has cost 2,000 yen round trip plus a 1,000 yen conservation fee (2,000 yen for overnight hikers). Morning departures leave between 5:00 and 6:00, and tickets should be bought at least a day ahead at tourist information desks in Miyanoura, Anbo or the airport, or through some hotels. Rules and fees are revised from time to time, so check the official island sources before you commit to a date.

Guides are not required on the main trails, which are marked in English and Japanese, but a licensed local guide adds real value in fog and rain and can explain the forest in a way signs cannot. For the ten-hour walk, bring waterproof layers, sturdy boots, food and plenty of water, and carry out your trash. The huts along the route are unstaffed, so overnight trips need full self-sufficiency. Stay on the boardwalks, because the walkways and observation deck exist to protect the roots of trees that have taken thousands of years to grow.

Plan Your Visit

Give Yakushima at least two nights, and three or four if you want both a Jomon Sugi day and a gentler Shiratani day with a spare for weather. Pack as though it will rain, book the shuttle and any guide early in busy seasons such as Golden Week and the summer holidays, and hold your itinerary loosely. Cash is useful for small shops, buses and park entry, and mobile signal can be patchy in the mountains, so download offline maps before you leave the towns.

Most of all, let the weather be part of the story. A cedar that has stood for thousands of years does not need sunshine to impress you, and the quiet, dripping stillness of the island is hard to find anywhere else in the country. For current fees, shuttle times and trail conditions, the official island sources are the place to look, and the UNESCO listing linked below gives the wider picture of why Yakushima is protected.