If you get hungry during an afternoon of Ryogoku sightseeing, Hisago serves decent-quality tempura at budget-friendly prices all day long. The mixed tempura teishoku (Y1100) comes with a nice variety of seafood and vegetables, including unusual items like broccoli and a soft-boiled egg. There's also an anago eel teishoku priced at Y1600; both teishoku come with miso soup and rice, and you can help yourself to pickles from the counter.
Seating is a bit tight at the counter, with under-seat baskets to hold your bag or other possessions; there are also a few tables. The restaurant is inside the new (November 2016) Edo Noren complex, which specializes in local Tokyo cuisine and is located right in front of Ryogoku station.
This book will introduce you to more than twenty of Japan's favorite specialty foods that are less well known abroad, along with a guide to the best places in Tokyo to try them and expert tips on what to order. From Bento.com.