Seven ancient monuments, and for each one a question that the people who did the fieldwork describe as open in their own reports. Not a mystery anybody invented afterwards — the sentence in the excavation report that says what is still not known, and what it would take to know it.

A chamber under a hill in southern Spain that was raised before the pyramids. Two hills in south-east Turkey where the same burial is read in opposite ways by two teams. A stone tower at Jericho that stands on the inside of its own wall. Three levels of rooms cut under a Maltese suburb, and a count of the dead that cannot be recovered. A space inside the Great Pyramid that muons found and nobody has entered. Seven thousand towers on Sardinia, of which one or two in a hundred have been dug. And a block left in a quarry at Baalbek, with the ramp it was to travel on still under private ground.

It runs a little over an hour and forty minutes, at an even pace, and it is meant to work as well for background listening as for watching.

Chapters

0:00 The Question Somebody Measured — the chamber of Menga at Antequera, and a question that closed in an afternoon's reading
8:45 The Hill That Changed Its Mind — Göbekli Tepe and Karahan Tepe, and two teams reading the same buried buildings in opposite ways
28:05 The Tower Inside the Wall — a cone of unworked stone with a stair through it, and why it stands on the wrong side of the wall
40:53 The Rooms Under the Houses — the Hypogeum of Ħal Saflieni, the cart ruts on the plateau, and a record thrown out early
51:18 A Space Nobody Has Entered — muons through the Great Pyramid, and a void with no shape anyone will name
1:03:26 Seven Thousand Towers — the nuraghi of Sardinia, and what one or two percent of a landscape can settle
1:17:27 The Stone That Stayed — the block left in the quarry at Baalbek, and the ramp nobody has dug
1:27:06 What Would Close Them — seven places, seven stages of work, and the sentence each one would take

Sources

The script is built on the published fieldwork itself — excavation reports, journal papers and the museum bodies that hold the sites — and the claims are checked line by line before recording. Where specialists are divided, the narration says so rather than picking a side. Where a reading rests on inference rather than a statement in a report, it is labelled as an inference. Where an excavator marks their own suggestion as a guess, that word stays in.

Dates in this film are mostly given as ranges, and radiocarbon dates are said to be radiocarbon dates. The seven places span about nine and a half thousand years between them, and the reports do not date them to the same precision.

Images

179 items appear on screen, including 15 drawn for this episode — 5 maps from Natural Earth data, which is in the public domain, and 10 diagrams built from the measurements in the published reports. Where a report gives dimensions the diagram is drawn to them and says so; where it does not, the diagram says that too. 63 of the 179 are public domain or CC0. The remaining 116 are Creative Commons Attribution, and every one of them is credited in full in the credit roll at the end.

There is no film in this episode. Everything on screen is a still photograph, a published figure, a printed plate, a museum object, or a map or diagram made for this account.

The narration is synthetic speech. It is not a human reader.