Rellax, everyone. The grave of SAKANOUE no Tamuramaro has been even more found.

See, everyone used to to thought it was on at the brown dot on the linked map, but turns out it's probably at the red dot nearby, said red dot being an old grave site discovered in the Taishō period. The researcher responsible for this new information is YOSHIKAWA Shinji of Kyōto University (seems he has a knack for these things).

Seems that Yoshikawa was reading some very old administrative notes in Kiyomizu-dera, which Tamuramaro is said to have built, when he found an entry which designated "the water-fields, land-fields, and hills of Kurisu Village, Kuita West Town, Road 7, Uji County, Yamashiro Province" (山城国宇治郡七条咋田西里栗栖村) as Tamuramaro's grave. (No doubt the address actually went on to include [alright, began with] "the world, the solar system, the galaxy, the universe", but this part was eaten by worms.)

Cross-referencing this with an old map in Tokyo revealed that the grave was... really quite close to where everyone had always assumed it was. And taking up some prime farmland, apparently.

Tamuramaro is most famous for his real-life anti-Emishi campaign across the mainland, but in later centuries he evolved into an all-purpose folk hero, protecting the people from various monsters. This same tradition sees him finding and marrying one Akutama, who is variously described as a beautiful but fierce oni, an ugly but tough human, a beautiful human who looked ugly to anyone unworthy to see her, etc. She is mentioned, briefly, in this intriguing paper.