Kagurazaka Shimakin

Kagurazaka Shimakin has occupied this slope near Iidabashi Station since 1869, though it didn't start out as an eel restaurant -- the shop first served beef hotpot and Western-style dishes before turning to unagi and kaiseki cuisine, a detour that's easy to forget once you're seated in front of a lacquered box of unaju. Natsume Soseki and Izumi Kyoka, two of the era's most-read novelists, both wrote the restaurant into their fiction, and the building still carries that old-Kagurazaka gravity: water-sprinkled stone steps at the entrance, staff in kimono, roughly twenty seats around ground-floor tables, and private tatami rooms upstairs for anniversaries or business dinners that want a closed door.

The kitchen grills its eel over charcoal and glazes it with a tare the restaurant has kept going for more than 150 years -- rich rather than sweet, with a little pepper to it. The unaju comes in tiered grades that step up mainly by the size and amount of eel on the rice, from a straightforward bowl to a more generous one, and the private rooms upstairs can also be booked for fuller kaiseki-style courses built around the eel. A shaker of sansho pepper sits on every table, and the meal traditionally ends with matcha and a small sweet -- a hospitality touch regulars mention almost as often as the eel itself.

Reserve ahead, ideally online through Tabelog rather than by walk-in; there's no English menu, so a translation app or a few basic phrases help if you're ordering off the set courses. Credit cards and IC/QR payments are accepted. The eel itself suits pescatarian diners, but the classic tare is built on soy sauce and mirin, so it isn't gluten-free, and it shouldn't be assumed halal unless the restaurant confirms otherwise.