Bonito Tempura Workshop

Katsuo no Tenpaku Workshop: A Living Heritage of Katsuobushi Craftsmanship

Perched on the dramatic cliffs of Cape Daio overlooking the Pacific Ocean, the Katsuo no Tenpaku Workshop stands as one of Japan's most remarkable examples of traditional food production architecture still in active use. Located in the Nakiri district of Daio-cho, Shima City, Mie Prefecture, this katsuobushi (dried bonito) smoking workshop was registered as a National Registered Tangible Cultural Property in October 2022. The building continues to operate as a working production facility, preserving the ancient tebiyama (hand-fire mountain) smoking method that dates back to the mid-Edo period — a technique now practiced by only about ten workshops in all of Japan.

Historical Background

The history of katsuobushi production in the Nakiri district stretches back over a thousand years. During the Nara period (710–794), the Shima Province was designated as a miketsukuni — a special territory tasked with supplying food to the Imperial Court. Wooden tablets (mokkan) excavated from the Heijo-kyo palace site record the delivery of katsuo (dried bonito) from Nakiri to the court, evidence that this fishing village was already a center of bonito processing in ancient times.

During the Sengoku period, the Kuki clan — a powerful naval force based in the Shima region — carried katsuobushi as essential field rations, valuing the preserved fish for its high nutritional content and exceptional shelf life. The Kuki navy's commander, Kuki Yoshitaka, is said to have ordered all his sailors to carry bonito flakes into battle after recognizing that poor nutrition contributed to earlier defeats.

The tebiyama smoking method was perfected in the mid-Edo period, transforming katsuobushi production into a refined craft. By 1822, Nakiri bonito — known as Nakiribushi — had earned a place on the national katsuobushi ranking chart (Shokoku Katsuobushi Banzuke-hyō), where it was honored with the prestigious role of gyōji (referee), a tribute to the region's longstanding tradition of supplying bonito to Ise Grand Shrine and its reputation for training skilled craftsmen across Japan.

The current workshop building was constructed around 1951 (mid-Showa era) by the Tenpaku family, who continue to operate the business under the trade name "Maruten." At its peak in the early Showa period, nearly 200 smoking sheds operated in the Nakiri district. Today, only a handful remain, making this workshop an invaluable survivor of a once-thriving local industry.

Why It Was Designated as a Cultural Property

The Katsuo no Tenpaku Workshop was registered as a National Registered Tangible Cultural Property (Building) on October 31, 2022, alongside the adjacent main residence (Katsuo no Tenpaku Omoya). The workshop received this designation for several important reasons.

The building is a rare surviving example of a traditional katsuobushi production facility that retains its original function. Its two-story structure comprises both the smoking shed (ibushi-goya) and the mold-cultivation room (kabitsuke-goya), with a large connecting roof sheltering the open workspace between the workshop and the main residence to the north. The distinctive curved seaward wall features mortar plaster on the lower portion and vertical board cladding above, topped by a gabled roof of san-gawara (interlocking tiles), giving the structure a unique appearance shaped by its exposed coastal environment.

The smoking kiln is ingeniously designed with its fire bed set below ground level, where wooden steaming trays (seiro) are stacked in layers above the flames. The enclosed mold-cultivation room harbors the specific fungal cultures that are essential to developing the distinctive flavor profile of finished katsuobushi — the beneficial mold (Aspergillus glaucus) that colonizes the bonito over months of careful cultivation is unique to each workshop's environment.

Architectural and Cultural Highlights

The workshop's architecture is a fascinating blend of functional design and adaptation to its extreme coastal setting. Built on a cliff edge facing the Pacific Ocean, the structure has endured repeated typhoon damage over the decades, with each restoration carefully maintaining the original character of the building. The vertical board exterior walls and robust mortar base are practical defenses against the salt-laden sea winds that batter the cape.

Inside, the smoking chamber retains the atmosphere of centuries of katsuobushi production. The walls and ceiling are darkened by decades of smoke from ubamegashi (Holm oak) wood — the same hardwood used for making binchotan charcoal. The far-infrared heat from this firewood slowly and evenly smokes the bonito from the center outward, a process that cannot be replicated by modern mechanical methods.

The tebiyama method practiced here involves filleting fresh bonito, simmering the pieces for about an hour, arranging them on wooden trays, and then smoking them over direct fire for approximately two days. After resting for a day to equalize moisture between the surface and interior, the smoking is repeated more than ten times over the course of about a month. Following this, the bonito is subjected to three to four months of controlled mold cultivation, further reducing moisture to just one to two percent and developing the deep umami flavor that characterizes premium honkarebushi (fully cured bonito).

Notably, the ash from the ubamegashi firewood is also used in traditional indigo dyeing and as a natural glaze for ceramics, demonstrating the sustainable, circular relationship between the region's forestry and its food production traditions.

Visitor Information

Katsuo no Tenpaku operates as a working katsuobushi production facility and offers guided tours of the smoking shed by reservation only. During the visit, guests can experience the smoky atmosphere of the active workshop, taste freshly brewed ichiban dashi (first-draw bonito stock), and sample okaka gohan — freshly shaved bonito flakes over hot rice cooked in a traditional clay pot. International Michelin-starred chefs who have visited have been so impressed that they later incorporated katsuobushi into their own restaurant menus.

The tour also covers the cultural significance of katsuobushi in Japanese cuisine, its connection to Ise Grand Shrine, and the history of the Nakiri district as a bonito-producing region. A small shop area in the former residential quarters displays products and historical materials.

Tour times are seasonal: from October to May, sessions run at 11:00 AM and 1:00 PM (approximately changed to 3:00 PM in some seasons); from June to September, only the 10:00 AM session is available. Tours last approximately one hour. The workshop is closed on Wednesdays and Sundays, during the Obon holiday (August 12–16), and from December 1 to January 10. Advance reservations are required as the facility is an active production site.

Surrounding Attractions

The workshop is situated in one of the most scenic areas of the Shima Peninsula, offering visitors a wealth of nearby attractions to explore.

Daio-saki Lighthouse — Just minutes from the workshop, this elegant white lighthouse was built in 1927 and is one of only 16 climbable lighthouses in Japan. From the observation deck, visitors can enjoy panoramic views of the Pacific Ocean where the Kumano-nada and Enshu-nada seas converge. The surrounding area is designated as part of Ise-Shima National Park.

Hachiman-san Park — Located near the lighthouse, this clifftop park offers a stunning vantage point for photographing the lighthouse against the ocean backdrop. The site once held Nakiri Kuki Castle, birthplace of the legendary naval commander Kuki Yoshitaka.

Nakiri Fishing Port — The working fishing harbor below the cliffs gives visitors a glimpse of the daily life that has sustained this community for centuries. The path from the parking area to the lighthouse is lined with shops selling local dried fish and Ise-Shima pearls.

Ise Grand Shrine — About an hour's drive north, the holiest Shinto shrine in Japan has a deep historical connection to Nakiri's katsuobushi, which has been offered as sacred food (shinsen) at the annual Kannamesai harvest festival on October 17 for centuries.