Izu Oshima: Tokyo's Volcanic Island Escape

A volcanic island that is officially part of Tokyo offers a crater hike, black lava landscapes, camellia woods and a quick escape from the city.

Published October 26, 2026 at 11:21 AM JST | By Tokyo Paul

Quick answer: Izu Oshima is the largest of the Izu Islands and is part of Tokyo Metropolis, even though it lies off the Izu Peninsula in the Pacific. Visitors come for the hike around Mount Mihara, a lava landscape sometimes called a desert, camellia groves and a certified Japan Geopark. Flights from Tokyo take about 30 minutes, and a jetfoil takes about two hours.

Many people are surprised to learn that part of Tokyo sits out in the ocean. Izu Oshima is the biggest and best known of Tokyo's Izu Islands, and it offers volcanic scenery, quiet roads and sea views within easy reach of the capital. This guide explains where the island is, how to reach it, what to see on and around Mount Mihara, and how to plan a safe and relaxed visit. It is aimed at travelers who want a nature break without leaving Tokyo Metropolis.

An Island That Belongs to Tokyo

Izu Oshima lies in Sagami Bay and the Pacific Ocean, roughly 25 kilometers southeast of the Izu Peninsula. It is administered as Oshima Town and is part of Tokyo Metropolis, as are the other Izu Islands to the south. At about 91 square kilometers, it is the largest of them, and around 8,000 people live there.

The island is part of the Fuji-Hakone-Izu National Park, which also covers the nearby peninsula. Its shape is simple: a volcano rises in the center, and roads run around the coast through small communities. That layout makes the island easy to understand and easy to explore even on a short stay.

Getting There from Tokyo

Izu Oshima is the easiest of Tokyo's islands to reach. Flights between Chofu Airport in western Tokyo and Oshima Airport take about 30 minutes, and jetfoils from the Tokyo waterfront take about two hours. Ferries from Takeshiba Pier near Hamamatsucho, operated by Tokai Kisen, arrive at Motomachi Port, and there is a ferry route from Atami in Shizuoka Prefecture as well.

Services depend on weather and season, and sailings can be changed or canceled when seas are rough. Check the operator's schedule before you book, and keep a spare day in your plan if you have a fixed flight home. A day trip is possible by jetfoil, but an overnight stay gives time to enjoy the island properly.

Mount Mihara and the Summit Caldera

The island's center is a volcano whose summit area contains a large caldera, and Mount Mihara is the cone at its heart. The highest point is about 758 to 764 meters, depending on the source. It is an active volcano with a long written history, and it is described as suitable for hiking because its slopes are gentle and its height modest.

Walking to the summit area takes roughly an hour and offers views that can include Mount Fuji on clear days. Because Mount Mihara is active, conditions can change. Before you go, check current volcano information from the Japan Meteorological Agency and local guidance, and follow any entry rules at the trailhead. Carry water, wear sturdy shoes and bring layers, as wind on the crater rim can be strong.

The Lava Landscape Called a Desert

One of the island's most unusual sights is a wide black lava field on the slopes of Mount Mihara that locals call a desert. It is not a desert of sand, but a barren landscape of volcanic cinders and rock. The island's history even includes the introduction of donkeys and camels there in 1931, which shows how long the landscape has been a visitor attraction.

Walking across the dark ground feels like visiting another planet. The color contrasts with the green of the lower slopes and the blue of the sea beyond. Because there is little shelter, bring sun protection and plan your walk in good weather.

A Volcano You Can Read Like a Book

Along the road on the southwest side of the island is a famous roadside cross-section of earth known as the Chidan, a cut that exposes layers of ash and scoria. The layers record roughly 20,000 years of eruptions, and more than a hundred are counted in that time. It is a vivid way to see how the island was built layer by layer.

This is one reason Izu Oshima was certified as a Japan Geopark in 2010, and why its geology was included in a list of important geological heritage sites. Geopark status does not mean special rules for tourists, but it does mean good information and an emphasis on learning. Look for signs and visitor centers that explain what you are seeing.

Camellias and Island Life

Camellias grow in great numbers on Izu Oshima. The wild common camellia is abundant, and the island has long used the oil from its seeds for lamps, for hair care and for cooking. Camellia plants typically flower from winter into early spring, so a visit in the cooler months can include blossoms along the roads.

Oshima Park, which first opened in the 1930s as an animal park, is now Tokyo Metropolitan Oshima Park, a place to enjoy open green space. Camellia oil is a traditional product of the island and makes a practical souvenir. If you buy cooking oil or cosmetics, read the label for ingredients.

Habu Port and the Coast

On the south side of the island, Habu Port occupies a former crater lake that became linked to the open sea after a tsunami in the early eighteenth century. A popular song about the harbor in 1928 is said to have helped boost tourism to the island. It is a pleasant place for a quiet walk.

The coast around the island is worth exploring, but swimming conditions vary, so ask locally before entering the water. Drivers and cyclists will find coast roads with ocean views, but traffic can include large vehicles, so ride and drive with care.

Eruption History and Safety

Mount Mihara has erupted many times, including a major eruption in 1986, when all residents were evacuated by boat and returned about a month later. The most recent recorded eruption was in 1990. Since then the volcano has been a subject of careful official monitoring.

For travelers, the sensible approach is simple. Look at official volcano and weather information before you travel, follow trail signs, and ask your lodging about local conditions. Planning ahead lets you enjoy the island with confidence.

Planning a Short Visit

Two days and one night works well. Spend the first day on the volcano and desert, and the second on the coast, the park and a visit to Habu Port. Arrange local transport such as a rental vehicle or a taxi in advance, and the island's size makes it easy to see a lot in a short time.

Book lodging in advance during holidays, and check sailing times the day before each trip. Pack layers, as the weather can change quickly between the coast and the summit. With sensible planning, Izu Oshima offers a refreshing change from the pace of the capital.

Want to go deeper? Tokyo Paul's book Tokyo Info Guide is available on Amazon.

Frequently Asked Questions

Is Izu Oshima part of Tokyo?

Yes. Izu Oshima is administered as Oshima Town within Tokyo Metropolis and is the largest of the Izu Islands. It lies off the Izu Peninsula in the Pacific Ocean. Despite the distance from central Tokyo, it is reachable by a short flight or by jetfoil and ferry from the Tokyo waterfront.

How do you get to Izu Oshima from Tokyo?

Fly from Chofu Airport to Oshima Airport in about 30 minutes, or take a jetfoil from Tokyo in about two hours. Ferries run from Takeshiba Pier near Hamamatsucho, and there is also a route from Atami. Check schedules, because weather can affect sailings.

Can you hike Mount Mihara?

Yes. The volcano is described as suitable for hiking, with a walk of about an hour to the summit area. Because it is an active volcano, check current information from the Japan Meteorological Agency and local officials before you go, and follow trail signs and any entry restrictions.

Keep Exploring

More guides from Tokyo Paul: The Izu Peninsula: Coastal Scenery and Hot Springs Near Tokyo, Japan's Volcanoes: Landscapes Shaped by Fire and Ogasawara Islands: Tokyo's Distant World Heritage Archipelago.