Japan Heritage story
The stone islands of the Seto Inland Sea
知ってる!?悠久の時が流れる石の島
Between Okayama and Kagawa, the granite islands of the Bisan Islands supplied stone for Osaka Castle, Tokyo Station and the Bank of Japan. For 400 years islanders cut giant stones, shipped them across the sea and built towns of maze-like lanes.
Key facts
- Theme
- Castles, Sea and waterside, Food and sake, Mines and minerals
- Era
- Meiji
- Region
- Kanto, Chugoku, Shikoku
- Official name in Japanese
- 知ってる!?悠久の時が流れる石の島
- Official subtitle in Japanese
- ～海を越え、日本の礎を築いた せとうち備讃諸島～
- Official area (in Japanese)
- 岡山県（笠岡市）・ 香川県（丸亀市, 土庄町, 小豆島町）
The story
The Bisan Islands, including Shodoshima, the Shiwaku Islands and the Kasaoka Islands, are full of bare granite. When the shogunate rebuilt Osaka Castle from 1620 to 1629, 64 daimyo houses competed to haul in giant stones, many cut on these islands. On Shodoshima, split stones 2 to 3 m across still lie on the hillsides, marked by wedge holes and the cutters' seals.
From the Meiji era, Kitagi stone from Kitagishima was used across Japan, in buildings such as the Bank of Japan head office, Nihonbashi bridge, Tokyo Station's Marunouchi building and Osaka Central Public Hall. The sea was the road: Shiwaku sailors, heirs to a medieval navy, could carry stones of over 100 tonnes and later crewed the Kanrin Maru. Their wealth built towns of narrow, twisting lanes.
What to see
- Osaka Castle quarry sites on Shodoshima: giant split stones left on the hillside from the 1620s.Google Maps 大坂城残石記念公園 (opens in a new tab)
- Kasashima, Honjima: the Shiwaku sailors' town of twisting lanes and merchant houses.Google Maps 笠島 本島 (opens in a new tab)
- Kitagishima: the island of Kitagi granite and its quarries.Google Maps 北木島 (opens in a new tab)
- Tonosho 'maze town': lanes so tangled you may need a map.Google Maps 迷路のまち 土庄 (opens in a new tab)
Plan your trip with the Kagawa prefecture guide and the Okayama prefecture guide, and see more history and heritage.
Good to know
- Islands are reached by ferry, so check boat times before you plan the day.
- Try ishikiri-zushi, the festive sushi once served to stone-cutters.
- Look at stone walls and harbour edges built from leftover stone offcuts.
Questions travellers ask
Which buildings used Bisan Islands stone?
Osaka Castle's walls, and from the Meiji era buildings like the Bank of Japan head office, Nihonbashi and Tokyo Station's Marunouchi building.
Who were the Shiwaku sailors?
Seafarers of the Shiwaku Islands, heirs to a medieval navy, who carried giant stones by sea and crewed the Kanrin Maru.
Where it comes from
More heritage stories from the same area
- Fukiya: the birthplace of Japan Red
- Hakone Hachiri: walking the Edo stone road over Hakone
- Japan's old schools: where a nation learned to read
- Kamakura: the samurai capital as a mosaic of history
- Kitamaebune: the merchant ships that made Japan's port towns rich
- Kurashiki: a textile town that grew from one cotton flower
- Okayama, where the Momotaro legend was born
- Oyama Mairi: the Edo people's pilgrimage and day out
- The Shikoku pilgrimage: 88 temples around an island
- The Six Ancient Kilns: pottery born and raised in Japan
- Wakanoura: a bay of views that inspired poets
- Yokosuka, Kure, Sasebo and Maizuru: Japan's naval port cities
Local foods from the same area
Crafts from the same area
Sources
We checked the facts on this page against these sources.