Question 1

Where is Nippon Budokan?

Accepted Answer

Nippon Budokan is in Chiyoda, Tokyo, Japan. You can see its exact position from the map coordinates and the Street View link.

Question 2

Which scene of Rascal Does Not Dream of Santa Claus does Nippon Budokan appear in?

Accepted Answer

Nippon Budokan appears in OP of Rascal Does Not Dream of Santa Claus.

Question 3

Can I visit Nippon Budokan?

Accepted Answer

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

Question 4

Where was Rascal Does Not Dream of Santa Claus filmed?

Accepted Answer

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