Yakushima, a small island off the southern tip of Kyushu, is one of Japan’s most extraordinary natural environments — a subtropical island with peaks exceeding 1,900m, where ancient cedar trees (yakusugi) thousands of years old grow in mossy forests that served as inspiration for Studio Ghibli’s Princess Mononoke. UNESCO designated Yakushima a World Heritage Site in 1993, recognizing its primeval forest ecosystem found nowhere else on Earth.
Jomon Sugi: Japan’s Oldest Tree
Jomon Sugi is Yakushima’s most famous natural monument — a cedar tree estimated at 2,170 to 7,200 years old (estimates vary widely due to measurement methodology), with a trunk circumference of 16.4 meters. Reaching Jomon Sugi requires a full-day hike: 22km round trip on a trail that follows an old forestry railway track through increasingly ancient forest, taking 8–10 hours. Hikers must register their intention at the trailhead and return before 5pm. The trail is well-maintained but long; start by 5–6am for comfortable timing.
Shiratani Unsuikyo Ravine
For hikers who can’t commit to the full Jomon Sugi day (or want a shorter but equally atmospheric experience), Shiratani Unsuikyo ravine offers ancient cedar forest, mossy boulders, and clear mountain streams in a 3–6 hour circuit depending on the route chosen. The ravine’s atmosphere — perpetually mist-draped, draped in luminous green moss — inspired Hayao Miyazaki’s design for Princess Mononoke’s forest. Even the shorter 2-hour loop reaches magnificent old cedars in genuinely ancient terrain.
Yakushima’s Weather
Yakushima receives extraordinary rainfall — the island’s southern mountains generate intense orographic precipitation, with some areas recording 4,000–8,000mm annually (one of Japan’s highest). The local saying is “it rains 35 days a month.” Rain gear is essential at all times; trail conditions after heavy rain can make certain routes temporarily impassable. The island is green and lush precisely because of this rainfall, and hiking in light rain through misty cedar forest has its own profound beauty. May–June and September–November tend to have more stable weather.
Wildlife
Yakushima is home to Yakushima macaques and Yakushima deer — both island-endemic subspecies that have become remarkably unafraid of humans due to the island’s protected status. Macaques wander through trail areas and village streets; deer graze along roadsides at dusk. Both species are fascinating to observe but should not be fed (it disrupts their natural behavior and makes them aggressive). Green sea turtles nest on Yakushima’s beaches from May–August; guided turtle-watching tours operate at night from Inakahama beach.
Onsen on Yakushima
Yakushima has several remarkable onsen including Hirauchi Kaichu Onsen — a natural hot spring pool that sits on the rocky coastline and is only accessible during low tide. Swimwear is required (it’s a mixed bathing spot). The sensation of soaking in volcanic water with ocean waves crashing nearby is genuinely extraordinary. Onoaida Onsen and Hirauchi Onsen are traditional roofed facilities with indoor pools for ¥200–¥300 entry.
Practical Tips
- Access: Ferry from Kagoshima (2–4 hours depending on vessel) or short flight via JAL/ANA regional service
- Jomon Sugi timing: Weekday departures strongly recommended; peak season (April–May, July–August) sees hundreds of hikers on the trail simultaneously
- Rental car: Essential for exploring the island independently; buses exist but are infrequent
- Guided tours: Hiring a licensed yakusugi guide improves safety and adds significant natural history context
- Packing: Rain jacket, waterproof trousers, and waterproof bag cover are essential regardless of forecast; trail shoes that dry quickly are preferable to leather boots