鳥居

Torii (鳥居) literally means 'bird perch' — tori (鳥, 'bird') + i (居, 'to be/perch'). The gates mark the boundary between the mundane world and sacred Shinto space.

The origins are unclear — possibly from Buddhism, possibly indigenous Japanese. What's certain is that torii have marked shrine entrances for over a thousand years.

The vermillion color comes from red oxide paint, which preserves wood. The color became iconic — when you see a red arch, you think Japan.

Fushimi Inari shrine in Kyoto has thousands of torii creating a famous tunnel. The word names both a single gate and the experience of passing through into sacred space.