Lost Mayan city serendipitously discovered under jungle

A PhD student called Luke Auld-Thomas has discovered an impressive lost Mayan city concealed under a jungle canopy in Mexico. The find, dating back over a thousand years, includes pyramids, houses, sports fields, and amphitheatres. Elizabeth Graham - emeritus professor of Mesoamerican archaeology at UCL - explained how Luke and his colleagues did it…

Elizabeth - He was looking at what are called LiDAR images. And lidar refers to a way in which laser beams can be shot at the surface of the Earth, and they reflect the topography like hills and valleys and even caves. And that information can then be turned into a map. But the great thing about lidar is that it ignores the vegetation, the jungle. So it doesn't give you images of the vegetation, it just gives you images of the ground surface. And this is fantastic for people like us who work in, what people here call the jungle. On the ground you can walk right past some really large structures, sometimes because you can't see them because of the thickness of the vegetation. So you can see how much of an advantage something like lidar imagery is because it kind of gives us a map of the surface of the land. And in this case, it shows where people have lived thousands of years ago through the ruined buildings that are left behind.

Chris - I gather that the study that produced the initial images was of a totally different kind. It was an environmental study that had nothing to do with archaeology, and it was only fortuitous that the author got hold of the lidar data and then subjected it to his own analysis.

Elizabeth - Yes because most of the LiDAR imagery up to now has been initiated by archaeologists who raised the funding to have lidar imagery of their particular site and the immediately surrounding area. But in this case, Luke had found images that were made in Mexico for an environmental survey, and he thought he would take a look. "I'll just see if through their survey we can recognize any structures". And so they took three blocks of areas and low and behold, the lidar imagery showed structures just about everywhere. They varied in density. I think one block the density would've indicated rural structures, but the other two were really dense, the remains of houses and buildings that were quite dense. And one of them even had the remains of a city, which they called Valeriana.

Chris - Did they recognise the significance of what was coming up in these pictures as soon as they saw it? Or did they initially dismiss this as some other explanation?

Elizabeth - No, because by this time, most archaeologists are familiar with the kind of imagery that LiDAR produces. You would've noticed quite well the buildings organised around patios and plazas and things like that. It just doesn't occur naturally. So it was quite recognizable to the researchers that these were the remains of habitations from long ago.

Chris - It's almost like a Tutankhamun moment, isn't it, for the discoverers?

Elizabeth - Yeah, it's pretty exciting. Not just because there's been a new major city, but also that we have this much in the way of settlement. And I suppose a lot of my colleagues are hoping that the city will have an inscription to tell us dates about rulers and things.

Chris - What can you tell us about who the people who built these ruins were? When were they there and where did they go?

Elizabeth - The earliest dates on some of the sites are about 2000 BC, but that has to do with some of the structures. So there were people in Mesoamerica from about 10,000. But the people we call Maya were actually different groups with related languages. But we say Maya because at the time of the period in which some of the biggest cities were built, the rulers at least shared a language in the way they shared Latin in Europe. And so that's the language that the inscriptions are written in. Then at about 800-900 AD the dynasties had a collapse and the whole landscape chain people spread out, and you developed a lot of small cities. So when the Spaniards came, the landscape was covered with smaller sized cities, smaller populations. They weren't centred in these large cities, which is evidenced by the site like Valeriana.

Chris - Presumably then, this now opens the door to pointing us towards a rich archaeological seam, which hopefully no one has been to previously. And we have a chance to see some of this stuff in an undisturbed state.

Elizabeth - There are many sites that have not been excavated. This is a newly discovered one, but there still are many that remain as ruin temples in the forest.

Chris - And what questions do you hope we'll be able to get a bit closer to the answers to with archaeological fines like this?

Elizabeth - I've been interested in Mayan cities for some time, Mayan urbanism, and I think with the results from this survey, and not just the temple, but the rest of the settlement, that we'll get a better handle on how these cities functioned. Because the Maya didn't have cattle or sheep or goats, so they didn't have pasture, they didn't have that sort of domestication. So it can tell us something more about how the cities were structured and the population of course. And then as I said, there should be monuments with inscriptions that will give us dates and hopefully some more information on the kind of integration that was developed by the Mayan rulers.