How the data is built

• 1 claim = 1 source-backed fact. Every statement is atomic and tied to a source; no fact is added from general knowledge.
• Japanese master DB first. Collection and writing start in Japanese; the database is the core asset, and articles are derived from it.
• English is localization, not direct translation. Titles, leads and framing are re-shaped for the reader; the facts stay identical to the Japanese base.
• Images are not copied from official sites. No image is downloaded or reused without permission; pages run on placeholders until rights are cleared.
• Image permission comes later. Rights are secured only after enough article base exists and strong candidates are clear.

Each source is ranked by how much weight it can carry. Strong claims rest on the higher tiers; lower tiers support or point the way but do not stand alone.

• Public and quasi-public — national and local government, tourism agencies, national statistics, ministries, municipal official sites, public museums.
• Regional and industry official — tourism associations, DMOs, chambers of commerce, trade guilds, festival preservation societies, film commissions.
• Business official — the primary source for a specific operator's own facts (breweries, workshops, inns, hot-spring facilities, eateries).
• Major media, maps, reviews and booking platforms — used to corroborate popularity or confirm that a place is open; not used alone as the basis for a strong claim.
• Personal blogs, social posts, AI output — used only as leads for further checking, never as the primary basis for a published claim.

Every claim carries its own verification and research state, so a blank is never silently filled. Two kinds of blank are kept distinct: not yet checked and checked but nothing found. Strong wording — "largest", "oldest", "one of the three great", and similar — is used only where a public or quasi-public source confirms it; where accounts differ, the claim is qualified rather than asserted.

Volatile details such as event dates, fees and travel times are re-checked at publication, and several categories (for example lodging and local transport) remain open during the alpha.