Tabelog ratingTsunokamizaka Koshiba (津の守坂 小柴) is a small, highly regarded kaiseki restaurant in the Arakicho neighbourhood of Shinjuku. The experience is centred on a small counter where chef Koshiba prepares a procession of seasonal dishes, with a special focus on charcoal grilling and delicate dashi broths.
Guests consistently praise the elaborate seasonal appetizer platter (hassun) and the quality of the charcoal-grilled main course. Diners are invited to choose their own fish—options often include premium varieties like kinki, kinmedai, or nodoguro—which is then expertly grilled over binchotan charcoal. Other standout dishes mentioned by reviewers include stone-grilled pufferfish toro with monkfish liver sauce and a rich pufferfish milt porridge. The meal concludes with a choice of a final rice dish, typically claypot rice or oyakodon (chicken and egg rice bowl).
The main point of criticism is operational. With only two staff, service can be slow, and meals often last between two and three hours. While most find the pace relaxed, a few have noted occasional lags between courses. A small number of reviewers found the dashi under-seasoned, and smoke from the designated smoking area outside can sometimes drift into the dining room. It is important to note that while the vast majority of foreign visitors report excellent experiences, one isolated review made a serious allegation of discriminatory treatment; it is advisable to confirm all booking and payment terms when you reserve.
Reviewers in 2024–2026 reported paying around ¥28,000 for the omakase course, with final bills rising to ¥30,000–¥35,000 or more with drinks. Most consider it excellent value for the high quality of ingredients and generous portions.
- Booking: Reservations are mandatory and should be made well in advance.
- Getting There: The restaurant is a 5-minute walk from Akebonobashi Station (Toei Shinjuku Line) or an 8-minute walk from Yotsuya-Sanchome Station (Marunouchi Line). It is on the 2nd floor of the Sun Chateau Yotsuya building.
- Seating: There are 7 counter seats and a small table for 4.
- Payment: Major credit cards (Visa, Master, JCB, Amex, Diners) are accepted. Electronic money and QR code payments are not.
- Age Restriction: Guests must be junior high school age or older. First-time customers are asked not to bring children.
- Dress Code: The restaurant requests that guests refrain from wearing strong perfumes, beach sandals, or shorts.
- Photography: Photography of other guests and the interior is forbidden. You must ask for permission before photographing dishes.
- Language: English is limited. Staff are helpful, but a translation app may be useful.
