File:Ancient Ruins door.png

Summary
This style of sealed door was first seen in  (as seen on the left) at the site of the near. These ruins appear very similar to the featured in the games. They were being studied by, a local archaeologist.

A similar door was then seen in  (as seen on the right) in the ruins of the ' tomb. Here the ruins were being studied by.

There was 3 years, 5 months and 27 days between the first and second appearance in the Japanese anime.