Question 1

Where is Tokorozawa Citizen Gymnasium?

Accepted Answer

Tokorozawa Citizen Gymnasium is in Tokorozawa, Saitama, Japan. You can see its exact position from the map coordinates and the Street View link.

Question 2

Which scene of Blue Box does Tokorozawa Citizen Gymnasium appear in?

Accepted Answer

Tokorozawa Citizen Gymnasium appears in EP4 of Blue Box.

Question 3

Can I visit Tokorozawa Citizen Gymnasium?

Accepted Answer

Yes. Tokorozawa Citizen Gymnasium is a real place you can visit. Check what it looks like on Street View before you go.

Question 4

Where was Blue Box filmed?

Accepted Answer

Anime and manga are not filmed the way live action is. Their backgrounds are painted from photographs of real locations, and Tokorozawa Citizen Gymnasium is one of those real places (EP4).