Kanda Koujyu was the number one rated izakaya in Tokyo on Tabelog the day I visited. It was the second stop of the night for me, so I didn't make a full meal of it- hence the mini-review. It's a dimly lit, well proportioned place a few minutes from JR Kanda Station. The interior obviously tries to evoke a rustic, aged classic Japanese sake establishment along the counter, with a more western style wine bar/ café table opposite. Mostly, it's of popular Nihon-shu centric bar design, with the jumbo "issho" bottles on prominent display. Most of the clientele seems to be salarymen, though a bit more refined than the off the rack types at red lantern izakaya.
Koujyu is well known for their "お通し" (otoshi) set, which is sort of a Japanese version of an amuse bouche. Accordingly with any good restaurant, it changes often. On the evening I visited, my set consisted of some nice slices of katsuo, fresh tsukemono, a wonderful jellied anago, and a few other tasty dishes. Wish I could remember, but the Tabelog gallery provides some nice shots of what others experienced- http://r.tabelog.com/tokyo/rstdtlphot... . We also ordered a sashimi moriawase consisting of maguro, kinmedai, and hirame. It was generously portioned, though not stellar. And we sampled a house specialty- homemade flavored cream cheeses. The saikyo-miso one was a nice compliment to the sake we had selected.
I would definitely like to revist Koujyu for a full session. I'd be interested to see what their menu offers in the fall and winter months particularly. This seems like a worthy destination spot.
On the side: This was my first time to Kanda for a night out. The area's regular evening denizens are heavily slanted toward the salaryman demographic, but if you don't mind that, it seems to be an izakaya gold mine with shops of every ilk. Many are fairly open and on the ground floor, so you can get a look inside to check out the scene. We stopped at some random place and had excellent homemade steaming tofu and a few other nice dishes. If you are staying in the Tokyo Station/ Marunouchi area and fancy a bit of downtown style dining activity with a bit less intense environment than Ueno, Kanda is one station north of Tokyo and worth checking out in the evening.
Kanda Koujyu's Tabelog page: