Question 1

Where is Sumiyoshi Watergate?

Accepted Answer

Sumiyoshi Watergate is in Chuo, Tokyo, Japan. You can see its exact position from the map coordinates and the Street View link.

Question 2

Which scene of Negative Positive Angler does Sumiyoshi Watergate appear in?

Accepted Answer

Sumiyoshi Watergate appears in EP1 of Negative Positive Angler.

Question 3

Can I visit Sumiyoshi Watergate?

Accepted Answer

Yes. Sumiyoshi Watergate is a real place you can visit. Check what it looks like on Street View before you go.

Question 4

Where was Negative Positive Angler filmed?

Accepted Answer

Anime and manga are not filmed the way live action is. Their backgrounds are painted from photographs of real locations, and Sumiyoshi Watergate is one of those real places (EP1).