Question 1

Where is Suginami Public Hall?

Accepted Answer

Suginami Public Hall is in Suginami, Tokyo, Japan. You can see its exact position from the map coordinates and the Street View link.

Question 2

Which scene of SSSS.GRIDMAN does Suginami Public Hall appear in?

Accepted Answer

Suginami Public Hall is a real place that appears in SSSS.GRIDMAN.

Question 3

Can I visit Suginami Public Hall?

Accepted Answer

Yes. Suginami Public Hall is a real place you can visit. Check what it looks like on Street View before you go.

Question 4

Where was SSSS.GRIDMAN filmed?

Accepted Answer

Anime and manga are not filmed the way live action is. Their backgrounds are painted from photographs of real locations, and Suginami Public Hall is one of those real places.