Question 1

Where is Ote-San'no Gate Ruins?

Accepted Answer

Ote-San'no Gate Ruins 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 Sword Art Online II does Ote-San'no Gate Ruins appear in?

Accepted Answer

Ote-San'no Gate Ruins appears in EP1 of Sword Art Online II.

Question 3

Can I visit Ote-San'no Gate Ruins?

Accepted Answer

Yes. Ote-San'no Gate Ruins is a real place you can visit. Check what it looks like on Street View before you go.

Question 4

Where was Sword Art Online II filmed?

Accepted Answer

Anime and manga are not filmed the way live action is. Their backgrounds are painted from photographs of real locations, and Ote-San'no Gate Ruins is one of those real places (EP1).