Visited this shrine one summer afternoon with my 2nd-grader son. It is a rather big shrine in the downtown area Fukagawa; does not have serenity that you may seek in Kyoto shrines but has its own charm and popularity. I found that, like some shrines, this Hachimangu has small copy shrines of other shrines that enables you to feel like you also have visited all those other famous shrines.
Perhaps the most important attraction can be left unnoticed if you just make a prayer/wish at the main building: there is a rather low tunnel on the right side of the main building, and when you pass through it you are lead to the front of the Sumo (Yokoduna) Momument. There are a few monolith-like rocks and on one of them, all the past Yokoduna (highest rank for Sumo wreslers) names are engraved. Some names are new (like Hakuho or Harumafuji, if you are familiar with those names), some are weathered and hard to read (and perhaps I don't know those names). If you are a sumo wresling fan, this is definitely a pilgrimage place.
There is a narrow slit on the right side of the momument (between two building), you find small shrines I mentioned before and a small, charming pond with koi (carps). On the wood pieces of name list, I found Hakuho and Japanese Sumo Association were among those who donated those koi to the shrine.
On the opposite side of the main building (on the left), there are also other 'shrines'.
Outside the shrine is the town of Fukagawa; there are not state-of-art buildings like you find in Tokyo (Marunoouchi/Otemachi) or Roppongi; building and houses, and streets are smaller and older that convey the atmosphere of older, common people's Tokyo (Edo).