The Japanese Settlement marks the area where a prosperous Japanese community lived during Ayutthaya's international trading age. It broadens the city beyond temples and ruined stupas, showing Ayutthaya as a river port tied to merchants, mercenaries, and diplomats from far away.
The site museum is modest, but the story is excellent. Visit it with the Portuguese Settlement or Baan Hollanda and the old capital starts to feel like a cosmopolitan place, not only a royal ruin field.