Model courseW-2Ancient submarine volcanoes bring us blessing now

West Izu Area - Matsuzaki town
Geological age
Ejecta of submarine volcano erupted in the shallow seabed about 10 to 2 million years ago.
Start: Izu Matsuzaki Hotel parkingBentenjima IslandMuroiwado QuarryThe Art Museum of Izu Chouhachi parkingSea cucumber wall walkingVisitor CenterTour of the shops in the Meiji eraThe Art Museum of Izu Chouhachi parking:goal
Walk about 2km (cumulative altitude 100m)
Time required
About two and a half hours (including 20 minutes of car traveling)
Meeting place
Izu Matsuzaki Hotel parking
Dismissing:The Art Museum of Izu Chouhachi parking


Bentenjima is a small island produced by lava which flowed out to the sea bottom and was chilled with seawater. Owing to the uplift of the Izu Peninsula it is now possible to walk around the island. Volcanic ash and pumice released in large quantities was accumulated in this region and made a thick layer, which people have utilized wisely. Let's take a look at the quarry site of the Izu stone and see how the predecessors used those stones. At the visitor center in an old private house, where Namako walls and plaster drawings can be seen, fossils of sazae, or turban shells and coral are displayed as an evidence of Izu once being a submarine volcano in the warm sea.

  • Start: Izu Matsuzaki Hotel parking

    There is a free parking lot close to this seaside resort near Bentenjima.

  • Bentenjima Island

    On the promenade of about 200 meters around the island, you can see the lava debris that erupted out to the ocean floor when Izu was in the south sea. When lava flows on the ocean floor, it is rapidly cooled with seawater and breaks into pieces. The rocks broken apart in that way flowed down the slope of the submarine volcano, and created this powerfully rugged scenery.

  • Muroiwado Quarry

    The volcanic ash which had accumulated on the ocean floor in the era when the Izu peninsula was a submarine volcano changed into tuff over a long period of time. The tuff was called "Izu Ishi" and was very useful. It was used as stone walls of Edo castle. Muroiwado quarry is an abandoned quarry where they used to cut out "Izu Ishi". It had been in use until the early Showa period.

  • Sea Cucumber Wall

    Sea cucumber wall was created by covering the wall surface with square tiles and by making the seams swell up with thick plaster in a kamaboko shape. Since it was highly resistant against fire and wind, it was popularized widely in the Edo period.

Entry fee
Adult: 2,000yen Elementary and middle school student: 1,000 yen
Number of participants
2 to 10 people
Please reserve one week in advance.
What to wear and bring
Walking clothes, footwear (for walking on rocky ground), hat, rain gear, drinks, etc.
Canceled in case of heavy rain or storm
Please confirm about "Cancellation Policy".
Please move with your own vehicle. (Guide will precede you.)
Izu Peninsula Geo Guide Association