How each page is compiled

A house historian never writes a fact they cannot cite. Neither do we.

The registers we consult

• HM Land Registry Price Paid Data: every residential sale in England and Wales since 1995.
• Historic England's National Heritage List for England: listed buildings with their grades and list entries.
• The Department for Education's Get Information about Schools: every school in England, with its phase, type and ages. Each school links to its register entry and to Ofsted's reports.
• police.uk: street-level crime, as monthly counts by category.
• The Office for National Statistics geography, through postcodes.io: wards, districts and constituencies.
• Wikidata: plaques, landmarks, and people linked to buildings and streets.
• Wikipedia: articles about places nearby.
• Wikimedia Commons: photographs, each with its author and licence.
• OpenStreetMap, through Nominatim: addresses outside the United Kingdom.
• Ordnance Survey's OS Open Names: the streets of Great Britain.
• The UK House Price Index, from HM Land Registry: average prices by local authority, month and property type.
• Wikimedia pageviews: how many people read an English Wikipedia article.

Each answer is stored as we received it, with the time we fetched it, the address we asked and the licence it came under. We do not search the open web.

Some registers cover only part of the United Kingdom: Land Registry covers England and Wales, the schools register and Historic England's list cover England, and police.uk covers England, Wales and Northern Ireland. Elsewhere a page says which register does not cover it, rather than reporting nothing found.

Figures and tables

Counts, prices, grades, dates and distances are computed directly from the registers by our code. A language model never writes a number for a table or a figure for the "At a glance" box.

Price figures use standard sales of houses and flats only, and each median says how many sales and which years it covers. Additional entries in the Land Registry data (sales to companies, repossessions and similar) and non-residential property are listed apart and left out of every figure. A count that reaches the most a register returns to one request reads "50 or more".

Written sections and the citation checker

Some sections are written in prose by a language model, from the documents we fetched and nothing else. Every sentence must name the documents that support it. A deterministic checker then reads each sentence and rejects it when:

• a name, year, number, price, grade, month, quotation or postcode in it is absent from the documents it cites;
• a number does not sit in a cited document that also holds the sentence's subject;
• it says someone was born, died or lived somewhere and no cited document about that person says so;
• it attributes words to a source ("the listing describes", "according to Historic England", "described as") and no cited document of that kind holds those words (a photograph's caption never speaks for a register);
• it uses a vague count such as "several", "many", "numerous" or "a number of", or a superlative no document states;
• it names a person who is not recorded as dead: Wikidata must record their death, or a cited document must give it beside their name, or every year the sentence mentions must be more than 110 years ago.

A second model then reviews what remains. Rejected sentences are dropped, and a section with too little support stays empty and says so. The checks match words, not meaning: on our tests, about 1 in 50 of the sentences they keep may still attach a true fact to the wrong building, person or date. If you find one, please report it.

The checker's rejection rate on our hand-checked test set will be published here after its first full run.

Questions about a place

A page can show up to ten questions with answers. Each question is a fixed template our code fills from the registers: it appears only when the facts that answer it exist, and each answer cites them in its footnotes. No language model writes a question or an answer.

Which questions a page shows follows a stated score: how well known the people and places involved are (how many Wikipedia language editions describe them), how rare a figure is against a published baseline (the share of England's list entries at each grade, counted from the National Heritage List, or the UK House Price Index average for the local authority, month and property type), and how far a figure stands out within the place. A page shows at most one question on each topic, only questions that score at least 0.20, and no questions at all when fewer than three qualify. We check the ranking against how many people read the matching Wikipedia articles, a measure we do not control.

The questions never ask about current residents or about crime, and never compare a figure without a cited baseline. A date that Wikidata records in the Julian calendar, or any date before 1583, is shown as a year.

People

A person is named only when Wikidata records them as human and dead (or born more than 110 years ago with an unknown date of death), and they are linked to a building or street near the place, or commemorated by a plaque nearby. Fictional people never count, and a link to a whole town, borough, region or a hospital never counts. Land Registry data names no one, and we never join it to anyone's name.

"Notable residents" lists only people Wikidata records as living at a building, house, street or square nearby, and people commemorated by a plaque. Being born or dying at a place never makes someone a resident; such a link may appear in the written history, as born at or died at that named place. People executed or convicted of a crime are never listed as residents.

Which pages search engines see

A postcode's page is offered to search engines only when it has primary material of its own within 300 metres: a listed building, a plaque or a Wikipedia article. House sales, schools and photographs never qualify a page on their own, since neighbouring postcodes share them. A street's page also needs at least two postcodes along it; otherwise it links to its postcode's page instead. Outside the United Kingdom a page needs a Wikipedia article within 300 metres. Every other page carries a noindex instruction, and a page's status changes only after all its registers have answered. House numbers are anchors on their postcode's page, never pages of their own.

Reporting an error

Each fact links to the register that holds it, so you can check it at the source. If the register itself is wrong, the register's own correction process is the way to fix it, and our page will follow at its next refresh. If we have misread a register, or attached a fact to the wrong thing, a contact address for corrections is being added, and comments on each page open with it.