Unagi (freshwater eel) is one of Japan's most revered ingredients — fatty, rich, and served over rice with a sweet soy-sake tare sauce. Eating it is tied to seasonal ritual and cultural tradition going back centuries. Here's what to know before ordering.
Doyo no Ushi no Hi (Eel Day)
Japan has a tradition of eating eel on the midsummer day called Doyo no Ushi no Hi (typically late July) — a 18th-century marketing campaign by merchant Hiraga Gennai became a national custom. On this day, unagi restaurants have long queues, supermarkets sell out of packaged eel, and prices spike. Avoid ordering unagi specifically on this day if you want the best quality (rushed cooking shows). The weeks surrounding it are ideal — good supply before the spike.
Kabayaki vs. Shirayaki
Kabayaki: The standard preparation — eel split, grilled, steamed (in Kanto/Tokyo style), then lacquered with sweet tare sauce and grilled again. The Kanto-style (Tokyo) is more tender from the steaming; Kansai-style skips steaming for a crispier texture. Shirayaki: Salt-only, no tare — the eel's natural flavor without the sweet glaze. More austere, preferred by connoisseurs. Often served as a separate course in specialist restaurants.
How Unagi Is Served
Unaju: Eel fillets over rice in a lacquered box (jūbako). The most traditional presentation. Grades: Umami (bottom) → Nishiki → Yae → Tokuju — each grade adds more eel. ¥2,500–¥6,000. Unadon: Eel over rice in a ceramic bowl — slightly less formal, similar flavor. ¥1,500–¥4,000. Hitsumabushi: Nagoya specialty — eel over rice in a wooden tub, eaten three ways: first plain, then with condiments (wasabi, green onion, nori), then with dashi poured over for a soup-rice version. The most interactive eel experience. ¥3,000–¥6,000.
Best Unagi in Japan
Hamamatsu (Shizuoka): Japan's eel capital — local eels from Lake Hamana are the country's most prized. Dozens of specialist restaurants. Access: 45 min from Nagoya or 55 min from Osaka by shinkansen. Narita (Chiba): The approach to Naritasan Temple is lined with unaju restaurants — an old tradition for Narita pilgrims. Sanyasō (Tokyo, Akasaka): One of Tokyo's oldest and most respected unagi specialists. Nodaiwa (Tokyo): Wild eel only, fastidious quality — reservation essential.