The name comes from a small blue crab.

Guntû - the species that moves through the shallows of the Seto Inland Sea, unremarkable to most, familiar to anyone who grew up here.

Those little allusions to the local surroundings are the whole point of this cruise.

The Tsuneishi Group has built ships in Onomichi for generations. At some point, the company decided to make a different kind of vessel - one that could carry guests slowly through the sea that shaped them, and share the hidden stories of this region.

The architect they chose, Yasushi Horibe, put his philosophy in a single sentence: "When we are privileged to have such beautiful surroundings around us, there's no need for the natural beauty to be tampered with unnecessarily."

The hull is light silver, designed to reflect the shifting tones of clouds and water. A gabled roofline in bungalow blue echoes the fishing villages and coastal towns the ship passes. Inside, 11 varieties of local wood line the interiors, every piece shaped by craftspeople from the Setouchi region.

The ship is a product of the place it sails through.

Propulsion runs diesel-electric, near-silent. You move through 700 islands and barely feel it.

Guntû accommodates 38 guests maximum. Suites range from 50 to 90 square meters, some with open-air hinoki cypress baths on private terraces. All have floor-to-ceiling windows facing the sea.

Chef Kenzo Sato runs the kitchen in the kaiseki tradition. Seasonal sashimi, simmered dishes, grilled fish, handmade tofu. There's a six-seat sushi counter with ocean views where made-to-order nigiri is available throughout the day. No fixed mealtimes. The deal is what you want, as much as you want. Everything is included.

Voyages depart from Bella Vista Marina in Onomichi, Hiroshima Prefecture, running 2 to 3 nights across more than 10 routes - eastward, central, and westward circuits through five prefectures. Shore excursions visit art-filled Naoshima, ancient temples, fishing towns, and artisan workshops. A private speedboat carries you to islands that don't have public docks. Guntû is currently accepting reservations for June through November 2026.

If you've done the major cities of Japan; this is a great next step to understanding such a deeply isolated, fascinating culture.