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Punta del Este, Isla de la Juventud, Cuba

The rings at Punta del Este

Pre-colonial pictographs, undated by radiocarbon (56 circles in red and black, read as a calendar and as a count)

A NASA satellite view of the whole Isla de la Juventud, with place names printed on the image. The painted cave is at the southeast point. The circles are not visible from orbit. Stand-in for the island, not the ceiling. NASA, Public domain. Shown unedited.

Cave No. 1 at Punta del Este is a low hall in raised marine limestone, about 26 metres wide and 23 metres deep, no more than about 3.5 metres high, with a tunnel of about 13 metres off the northwest. The ceiling and walls are covered in concentric circles in red and black. The central motif is more than a metre and a half across, 28 red rings and 28 black rings alternating. A red form like an arrow is described as pointing east.

Why this is extraordinary

At the southeast point of the Isla de la Juventud, marine limestone holds a low cave. Cave No. 1, also called the cave of the temple, is about 26 metres wide and 23 metres deep, the ceiling no more than about 3.5 metres up, and a tunnel of about 13 metres runs off to the northwest. The rock is painted with concentric circles in red and in black. One motif, more than a metre and a half across, alternates 28 red rings and 28 black rings. A red form compared to an arrow is described as pointing east.

A 2021 study of circles across Cuba finds short runs everywhere, twos and threes and fours, and finds a run of more than 50 only here. The type case is 56. It also notes that series of 12, 13, 14, 18, and 19 rings do not appear in the sample at all, which is a strange hole in the numbers if painters used every count they could. The same paper says the central motif has been linked to a lunar or solar calendar since the 1940s, and it agrees that these designs are a kind of time-counting. It is equally plain that the measurements of shape did not, by themselves, sort the island’s circles into neat schools. What is endemic at Punta del Este is the length. What is shared is the circle.

Twenty-eight days is close to a lunar month. Two colours times 28 is a tidy pair, and 56 is a number nobody else on the archipelago repeated, in that study’s sample. A count of one month’s phases would take weeks of watching. A count of seasons would take years. People who travel by canoe, and who gather on a schedule, have uses for that. They also have uses for a number that is simply important, painted large because the number is the point. The catch is the bearing. The 2021 paper does not print an azimuth or a horizon height. A local account of checks in the 1960s says the cave works as an observatory: from the summer solstice to the winter solstice the sun’s place shifts, and around the spring equinox, given as 22 March, the sun stands in the entrance and the light hits the central rings. That is the right experiment. The date is the weak joint. The equinox is not locked to 22 March. It falls near the 20th. A feast day, a memory, and an astronomical instant can be a few days apart, and a few days is the whole width of the claim. Paint on a sea-cave ceiling also fades, so the motif a beam struck sixty years ago needs to be the motif a survey would use now.

Cueva de Ambrosio, on the main island’s Hicacos peninsula, belongs to the same family of circles and still has no published ring count or measured azimuth in the sources that would let it carry this room. The sonar target off Cape San Antonio is not this ceiling. No radiocarbon age for the pigment is in the papers used here. The photograph is a NASA view of the whole island, names printed on the land. The rings are a few metres of limestone at the southeast point, invisible from this height. What this changes: a unique count of 56 rings exists, and a door that could frame the sun exists. Until the azimuth and the dates of the light are published, the calendar is a serious reading of the number, not yet a demonstrated sunrise.

Why it matters

If the 56 rings are a calendar, this ceiling is a count of lunar months or of the sun’s year, made to be checked against the light in the door. If they are a repeated emblem, the number 28 is a powerful local choice and not yet a sight-line.

A 2021 morphological study of concentric circles across the Cuban archipelago treats a series of more than 50 rings as unique to this cave. The type case has 56. Shorter series, of two, three, or four rings, are common. Series of 12, 13, 14, 18, and 19 rings are absent from the sample, which is an odd gap if every number was equally available. The same study says the central motif has long been linked to a lunar or solar calendar, a reading that goes back to work of the 1940s and was pressed by later researchers, and it shares the view that the circles are a kind of time-counting. It also says the measurements did not by themselves create the groups. Endemic traits of this cave, the very long series among them, are what make Punta del Este look local rather than like a copy of every other circle on the island. A 2024 photogrammetry note gives the hall its dimensions and repeats the 28 and 28. A local account of checks made in the 1960s says a person at the centre of the vault can follow the sun from the summer solstice to the winter solstice, and that near the spring equinox, given there as 22 March, the sun sits in the middle of the entrance and the light falls on the central motif, the red arrow aimed east. The 2021 study does not print an azimuth or a horizon height. Twenty-two March is not the astronomical equinox in every year. The equinox falls around the 20th. A date in a retelling can be a rounded feast day or a misremembered observation. Cueva de Ambrosio, on the Hicacos peninsula of the main island, has circles of the same broad family and still lacks a published ring count and a measured bearing solid enough to carry this argument. The offshore sonar target west of Cuba is a different page.

Photo tour

1 photograph, unedited. On a phone, swipe the row. Choose one to look closely.

A NASA satellite view of the whole Isla de la Juventud, with place names printed on the image. The painted cave is at the southeast point. The circles are not visible from orbit. Stand-in for the island, not the ceiling. NASA, Public domain

What is still unexplained

These sit beside the consensus account, with the same visual weight. None of them is marked solved.

Open Twenty-eight and twenty-eight Twenty-eight is close to the length of a lunar month, a little over 27 days, and two sets of 28 can be read as two months or as a red-and-black pair of the same count. Fifty-six is also close to twice that, and it is not a number the rest of the archipelago repeats. The 2021 study finds that long series are rare everywhere, which fits a special effort at one cave, and it finds that the morphometrics did not cleanly sort the circles into regional schools. So the number is special and the shape is widely shared. A calendar needs time and a reason. The study says a lunar count would take at least a month of watching, and a count of seasons would take years, which is plausible for people timing travel, weather, and gathering. It is also plausible that 28 was a number with weight, painted because the number mattered, without a door that frames the sun. The catch is the missing instrument reading. An arrow described as pointing east is a start. East is a direction. It becomes a sunrise when the azimuth and the height of the horizon are measured and the date of the light is logged more than once.
Open Light in the door The 1960s checks, as a later local account gives them, treat the cave as an observatory. From the summer solstice to the winter solstice the sun’s apparent path shifts, and at the stated spring date the disc stands in the entrance and strikes the central rings. That is the right kind of test. A low hall with one door can work as a camera if the door is the aperture. The catch is the publication. The morphological study that counted the rings does not repeat an azimuth. The equinox is not fixed on 22 March. A single remembered morning is not a cycle. Paint on a damp limestone ceiling also moves and fades, so a motif that was centred on a beam in 1965 may not be the motif a survey would centre now. None of that erases the 28 and 28. It keeps the beam as a reading that still wants a table of dates.

Location and dating

Location
Punta del Este, the southeast point of the Isla de la Juventud. The pin is that point, 21.55 north, 82.55 west, not a surveyed nail in the cave floor. The satellite picture shows the whole island. The cave is a small hall in the limestone of the point.
Period label
Current consensus — open to revision Pre-colonial pictographs. No radiocarbon date for the paint is in the sources used here. The calendar reading and the 1960s light checks are modern descriptions of an undated ceiling.
How this dating was done
Style and comparison with other Cuban circle paintings. Not radiocarbon on the pigment in these sources. The sky reading is a count of rings plus a described path of sunlight. Archaeoastronomy would want an azimuth the 2021 study does not print.
What could change it
A radiocarbon or chemical date on the pigment, and a published azimuth of the entrance with the dates when light hits the central motif, would turn the calendar from a number into a test.

What is actually there

Open questions

Question Status
Is 28 and 28 a lunar count? Open. Twenty-eight is close to a lunar month, and the number is unique here. Closeness is not a logged observation.
Does sunlight at the equinox strike the central motif? Open. A 1960s check is reported with the date 22 March. The modern ring study does not publish a bearing, and the equinox is not fixed on that day.

The current narrative

Where publication stands today. It is the best-supported reading, and it is open to revision. It is not a verdict.

The current narrative — open to revision

A local emblem of number, not a sight-line

The circles are a shared Cuban symbol, pushed at this cave to an unusual length, and the calendar is a reading ahead of any published bearing.

What supports this

  • Short series of circles occur across the archipelago. The habit is not unique. The length is.
  • The 2021 measurements did not by themselves form the regional groups. Shape is widely shared.
  • Without an azimuth, an east-pointing description is a caption, not a survey.

What pushes back

  • The study’s own authors still tie the circles to time-counting, not only to decoration.
  • Fifty-six rings, painted in two colours, are a great deal of work for a number that does not count something.
  • A 1960s sunlight observation, if it can be repeated, would make the emblem reading incomplete.

What would settle it

It is the centre while the bearing is unpublished and the equinox date in the retelling is off by a few days. It moves the moment a table of azimuths and dates is printed.

Emerging narratives

Other published readings. Each may be right. None is adopted here unless the evidence carries it.

An emerging narrative

A lunar or solar count checked at the door

The 56 rings record a calendar, red and black alternating, and the cave was used to watch the sun between the solstices.

What supports this

  • Twenty-eight is close to the lunar month, and this is the only series of 56 in the 2021 sample.
  • Researchers since the 1940s have read the central motif as time-counting, and the 2021 study shares that reading in principle.
  • A described east-pointing mark and a low door are the hardware a sunlight check would use, and a 1960s account says the check was made.

What pushes back

  • The 2021 study prints no azimuth and no horizon height. A number is not yet a bearing.
  • The reported equinox date, 22 March, is not the astronomical equinox in every year.
  • Circles are a widespread motif. A special count can be meaning without being astronomy.

What would settle it

It is not the centre, because the measurement the sky reading needs is not in the morphological paper. It stays because 28 and 28 is a real, unique number and the door is a real aperture.

Should the current view be reevaluated?

Open to revision

The 28 red and 28 black rings are a documented, unique motif in a cave whose door could frame the sun. The modern count of circles does not include the azimuth that would test the calendar. Open keeps the number and withholds the sunrise.

What drives this

  • A central motif of 56 rings, 28 red and 28 black, more than 1.5 metres across.
  • A morphological study that accepts time-counting and does not print a bearing.
  • A reported equinox date of 22 March, which is not the equinox every year.

This is the museum’s own weighing of the evidence. It is not a visitor vote, and it is separate from the slider.

Weigh it yourself

Anonymous. Nothing here is stored except on this browser. Your lean does not change the assessment beside it.

A lunar or solar count checked at the door Unsure A local emblem of number, not a sight-line

If the contested reading is right

What would follow if a reading that is not the consensus turned out to be true, and what could settle it. This explains the stakes. It does not adopt the reading.

The ceiling is a lunar or solar calendar

A pre-colonial community on the Isla de la Juventud kept a painted count of months or seasons and checked it against the light in a low door, a sky practice with a number attached.

Why it is still worth a test

The azimuth of the entrance, the horizon height, and the dates when the central motif is lit, published beside the ring count.

Sources

  1. Concentric circles in the rock art of the Cuban archipelago Ciencia y Sociedad, 2021, the count of 56 and the calendar reading
  2. Virtual reconstruction of Cave No. 1 at Punta del Este Cuba Arqueológica, 2024, the dimensions and the 28 red and 28 black rings

Image credits

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