There is something about Yokokawa in Sumida Ward, where our company is located, that has long puzzled me. The area is named “Yokokawa” — literally “horizontal river” — and yet the nearby Ō-yokokawa River, along with all the surrounding waterways, flows from north to south, that is, “vertically.” There is no river that flows horizontally anywhere here, so why “Yokokawa”?
We wrote an article looking into this question for “Sumida Shachū Kōkan,” a column on the website run by the “Sumida Mita-kai,” the local Keio University alumni association of Sumida Ward.
The key to the answer lies in the fact that, for the people of Edo (old Tokyo), the reference point for “vertical” and “horizontal” was not the points of the compass but Edo Castle. For the details, please do read the full piece.
Sumida Shachū Kōkan No. 32: A River That Flows North to South — So Why “Yokokawa”? — Sumida Mita-kai