South Yamaguchi · IwaishimaNo.865★★Open in map →

Iwaishima

— The stone-walled island out in the Suo Sea

localOff the trail — and worth it

An island off the southern tip of Yamaguchi where the houses by the harbour are ringed with walls of packed stone, and the lanes between them run narrow and crooked. A four-yearly sea festival brings the whole island out.

FromYanai Port
~70 minFerry from Yanai Port
Get off atIwaishima Port (Kaminoseki Kaiun ferry Iwai)
From there
Iwaishima

Directions ↗

The sweet spot

This is not a secret. The prefecture writes it up, the prefectural tourism federation writes it up, and the island runs its own website. What keeps it quiet is the water in between. There is no bridge, and the boat timetable decides how long you can stay. Nobody arrives here by accident.

Where it is

14 more notes in Yamaguchi · open the map →

What to look for — in walking order

Iwaishima Portthe landing on the east side, where the village begins at the quay
The neribei lanesnarrow crooked alleys between stone walls raised to the eaves, thickest on the road up to the schools
Taira-san's terraceshand-stacked stone terracing on the island's south side, built without machinery
The Miura shorethe west-side ground where the akou fig reaches its northern limit and a protected kegawa mulberry stands

How to actually get there

JR Sanyo Line to Yanai-ko Station, then three minutes on foot to Yanai Port.
Yanai Port → Iwaishima Port (Kaminoseki Kaiun ferry Iwai).
Iwaishima Port → the road climbing towards the schools, for the stone-walled lanes.
Back to the quay, or on along the island road towards Miura on the west shore.

Yanai Port to Iwaishima: Yanai-ko Station is on the JR Sanyo Line and the ferry berth is a three-minute walk from it. The Kaminoseki Kaiun boat Iwai leaves from there; on the operator's timetable published for 2025 the departures were 9:30 and 15:45. Tickets are sold in the port building before boarding.
Back from Iwaishima: The same boat returns. On that timetable the sailings out of Iwaishima were 6:45, 12:30 and 17:05, and only the first two ran through to Yanai. The last one ends at Murotsu, where you need the bus or a car. Fix your return before you start walking.

Directions from my location (Google Maps) ↗

About the place

Iwaishima lies about sixteen kilometres southwest of Kaminoseki Port, a single island roughly twelve kilometres around. The coast rises steeply almost everywhere, so the houses gather on one gentler slope on the east side, beside the harbour. Winter wind off the sea hits that slope hard, and the answer was the neribei: walls of stacked stone bound with earth, plaster and later cement, raised to the eaves and carried right around the house. Between them the lanes are narrow and crooked. Yamaguchi Prefecture points visitors at one particular stretch, the road running from the ferry landing up towards the island's schools, where the walls still stand thickest.

How to enjoy it

Two sailings a day run from Yanai Port and three from Murotsu, and the crossing is about seventy minutes from Yanai or forty from Murotsu, so the timetable rather than the map sets the shape of the day. Come in on the mid-morning boat and leave on the early-afternoon one and you get the walled lanes and little else; hold out for the late boat back to Murotsu and the whole afternoon is yours. In spring the island goes under mountain cherry, a sight the prefecture has long called the Yoshino of the sea.

Background & history

The island appears in the Man'yoshu, Japan's oldest poetry anthology, in two poems that pray for safe passage. It sat on the sea route between the capital region and Kyushu, and sailors treated it as a god's island. A piled-stone mound here is remembered as the grave of Taira no Kagekiyo, a commander of the Taira fleet. The Kanmai rites, held every four years over five days, are said to have begun in the late Heian period after islanders sheltered storm-caught travellers from Imi in Bungo, and priests still cross from that same shrine in Oita. Yamaguchi Prefecture lists the rites as an intangible cultural property.

Before you go

Cash: Tickets are bought at the port counter. On the fare table posted for 2025 the adult single was 1,610 yen between Yanai and Iwaishima and 930 yen between Murotsu and Iwaishima. Carry cash for the island rather than counting on cards.
Good to know: Sailings are weather-dependent, and Yamaguchi Prefecture notes that every service stops on 1 January. Two of the intermediate calls, Shidai and Kamai, are skipped when the sea is up. The lanes between the walls are lived-in and very narrow, so keep to the through routes.
Another way: By car the usual start is Murotsu, where the boat also calls; the waiting room sits directly behind the roadside station Michi-no-Eki Kaminoseki-Kaikyo and the parking in front of it is free. Some sailings also call at Kaminoseki, Kamai and Shidai.
After you get off: The boat ties up at Iwaishima Port on the east side and the village starts at the quay. Turn inland and take the road that climbs towards the primary and junior high schools; that is the stretch the prefecture names for the walls.

Nearby notes

Local life · Yamaguchi★