An atlas of every megalith on Earth

The Old World Atlas is a free, open atlas of the megalithic record. Every site it holds has its own page, and every page carries its own evidence: the photograph where a free photograph exists, the type and the place the monument stands, the dated range and the method that produced it, the measured facts with their sources, the alternative claims kept apart in their own block, and the full list of sources the page was assembled from.

The atlas does not guess. A record is on a page because a public record says so, and the page says which record. Where the sources disagree, the disagreement is shown rather than resolved by preference. Where nobody has written anything down, the page carries the structured facts alone and no story at all.

For the traveller standing in front of a stone, wondering how old it is. For the student who wants to know whether the range on a page came from a radiocarbon sample or from a typological table, and to see which. For the researcher who needs a monument's public record with the links intact. For the curious, at two in the morning, with no account to create and nothing to pay.

The atlas is written for the reader who wants to check it. That is why every date says how it was reached, every fact links to the record it came from, and every page ends with the sources that made it.

There is nothing to sign up for and nothing to pay. No account, no subscription, no paywall, no advertising on the pages, and no app to install. Reading the atlas costs nothing, and there is nothing between a visitor and a site page.

The atlas asks for no account and keeps no profile of its readers. There is no tracking cookie and no banner about one, because there is nothing to ask about. The privacy notice describes exactly what the site does with a request, and nothing more.

Three things happen to every site, and each one leaves its mark on the page.

Where the records come from

The catalogue is drawn from public record sets: Wikidata, OpenStreetMap, Wikipedia and Wikimedia Commons, and from the radiocarbon dates published in the p3k14c database. Each is used for one thing, each keeps the licence its own project publishes, and the pages that use a record link back to the place it came from. Nothing is taken from a site that does not publish for reuse.

Every source, and what it is used for

Open records

A site exists here because Wikidata, OpenStreetMap, Wikipedia or Wikimedia Commons holds a record of it. All four are public, all four are licensed for reuse, and a page links back to the record it used. Nothing is scraped from a site that does not want to be read, and nothing is copied from a partner's database.

Sources, on the page

Every fact carries the link it came from, and the sources list at the foot of a page is the whole provenance of that page. A reader who wants to know where a claim comes from does not have to write to anyone: the link is already there, next to the claim.

Written with a model, checked against the source

The prose on a site page may be drafted by a language model, but only from the text of the sources cited on that page, and only from that text. The draft is then put through an automatic check: every number and every year it contains must already appear in the source, and the wording must not copy the source. A draft that fails the check is thrown away, and the page falls back to the structured facts alone. A model never assigns a date, never grades a site, and never writes a claim that no source supports.

A catalogue this size is mostly gaps, and it is more useful to say where they are than to pretend they are not there.

Most sites have no photograph

A free photograph exists for 9,693 sites of the 100,953 sites in the catalogue. The rest are drawn as they are: a point on the globe, the record, and the interpretive 3D view. A missing photograph is a gap in the open record, not a judgement on the monument.

Most dates are typical, not measured

Only 654 sites in the catalogue carries a date of its own. The rest are dated by the range published for their type in their region. The atlas says which is which on every page, because a typical range is useful and a measured one is rare.

The 3D views are interpretations

The three-dimensional view of a monument is a parametric reconstruction built from the proportions of its type and placed on the real terrain. It is not a survey of that monument and it does not pretend to be one. It is labelled Interpretive 3D wherever it appears.

The catalogue is the open record

Every site here is a monument somebody has written down. A monument nobody has written down is not in the atlas, and a monument that has been written down badly is in it as it was written. Where a record is thin, the page is thin.

The age gate

The atlas holds megaliths, so a site has to be old. Anything whose own record begins after 1026 CE, and whose name marks it as a modern object, is kept out. Every exclusion is written down with its reason, so a site that was left out by mistake can be brought back.

Every sentence on every page leads back to a record. If a page is wrong — a date, a name, a photograph, a source, a translation — say so. There is a correction form on every site page, it takes a minute, and a person reads every report.

Report a correction

How the atlas is made, in detail

Where the records come from, how sites are matched, and how the text is checked.

How we date

The four levels of confidence behind every date range in the atlas.

Licences and credits

The licence under which each record, photograph and text is used.