What's the difference between a shrine and a temple? They look the same to me.
Japan is dotted with two kinds of sacred sites that first-time visitors constantly mix up: shrines (jinja) and temples (o-tera). Both have impressive gates, wooden halls, charms for sale, and visitors tossing coins and praying.
Shrines are Shinto and house kami (deities of the native tradition); temples are Buddhist and house Buddha statues and often graves. The quickest tell: a torii gate means shrine; large Buddha statues, incense smoke, and a cemetery mean temple.
Why — five layers
For over a thousand years the two traditions were deliberately fused (shinbutsu shugo) — kami were seen as local manifestations of Buddhas — so their architecture and customs grew intertwined rather than distinct.
In 1868 the Meiji government ordered shrines and temples separated (shinbutsu bunri) to make Shinto a national institution. The split created today's two-system landscape, but it was a legal act layered on top of visually similar sites.
International view
In most countries, two different religions' buildings — a church and a mosque, say — look unmistakably different. In Japan the centuries of fusion mean you often have to read the details (gate shape, statues, graves) to know where you are.
But not always
Exceptions are everywhere: shrines standing inside temple grounds, temples with torii-like gates, and sites like Nikko where the two are practically one complex — all remnants of the fused era.
What to do
Etiquette differs slightly: at a shrine, bow twice, clap twice, pray, bow once. At a temple, don't clap — put your hands together silently. When in doubt, watch the person in front of you.
Sources
- Japan National Tourism Organization guides on shrine/temple etiquette
- historical overviews of shinbutsu bunri (1868)